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Full text of "Negretti & Zambra's encyclopædic illustrated and descriptive reference catalogue of optical, mathematical, physical, photographic and standard meteorological instruments, manufactured and sold by them .."

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©ptidans  ani  jJrientifit  Jfnsirununt  Utabrs  to 


H.R.H.    THE     PRINCE     OF    WALES; 




45,    COBNHILL,    E.G.,     and    122,    REGENT    STREET,    W., 


Revised  and   Corrected  Edition. 

Oi          vvv^ 



LONDON.     E.G. 

photographers  to  tbe  Crystal  palace  Company 






Are  open  daily,  and  Portraits  taken  in  all  the  most  approved  Styles,  from 
Carte  de  Visite  to  Life  Size. 



All  kinds  of  Photographic   Work   undertaken,  and  executed 
with  ability  and  despatch. 

Price  Lixts  Posted  Free. 

XEGRETTI  &  ZAMBRA  have,  in  connection  with  their  Photographic  Rooms 
in  the  Ceramic  Court,  Crystal  Palace,  a  department  for  the  sale  of 
Optical,  Meteorological,  Philosophical,  and  Photographic  Instruments; 
and  respectfully  invite  inspection  of  their  extensive  stock,  conveniently 
arranged  for  examination,  every  facility  for  so  doing-  being-  afforded  by 
the  Assistants  in  attendance. 

Opticians  anfc  meteorological  instrument 



H.  R.   H.     THE     PRINCE     OF     WALES 

A   SPECIAL  PRIZE  MEDAL  was  awarded  at  the  International  Exhibition 

of  1 862  to  Negretti  and  Zambra  ;  and  the 

AUSTRIAN  GOLD  MEDAL  was   also  presented  to   the    Firm  for  the 








1851.  The  only  Prixe  Medal  for  Meteorological  Instruments 
was  awarded  to  Negretti  and  Zambra. 

1855.     "  Honourable  Mention."— Paris  Exhibition. 

The  £ew  Committee  exhibited  among  their  Apparatus  one  of 
-A7".  <$[  Z*s.  Patent  Maximum  Thermometers  ;  the  Jury  awarded  an 
Honour  able  Mention  for  this  Instrument.  Negretti  and  Zambra 
not  having  exhibited  at  all. 

The  "Austrian  Gold  Medal." — For  Stereoscopic  Photographic 
Views  on  Glass.  ^ 

1862.  Two  Prize  Medals. — J.  Meteorological  Instruments. — The 
terms  of  the  Award  being  as  follows  : — "  For  many  important 
inventions  and  improvements,  together  with  accuracy  and 
excellence  in  objects  exhibited." 

II.     Photographic  Transparencies,  "for  beauty  and  excellence 
of,  and  adaptation  of  Photography  to  'Book  Illustrations" 

1875.  A  Prize  Medal. — Santiago,  Chili,  awarded  for  their  exhibited 
collection  of  Optical  and  Physical  Instruments. 

1876.     Three  Prize  Medals.— Philadelphia,  "/or  Meteorological 
Instruments  ;  "  "for  Thermometers"  and  "for  Microscopes  J*' 

1878.    A   Gold  Medal,  Paris.     The  only  Gold  Medal  awarded 
for  Meteorological  Instruments  in  the  British  Section. 

Fisheries  Exhibition,  Norwich.  A  Silver  Medal  and 
Diploma  for  Deep  Sea  Recording  Thermometers  and  Sextants. 

Fisheries  Exhibition,  Edinburgh.  A  Silver  Medal  for 
Deep  Sea  Recording  Thermometers,  &c. 

Buitenzorg,  Batavia,  Java  Exhibition.  A  Gold  Medal  for 
general  excellence  of  Optical  Instruments  exhibited. 

International  Fisheries  Exhibition,  London.  A  Gold 
Medal  for  Meteorological  Instruments.  A  Silver  Medal  for 
Deep  Sea  Recording  Thermometers.  A  Bronze  Medal  for 
Current  Meter.  A  Gold  Medal  for  Standard  Barometers. 

International  Health  Exhibition,  London.  A  Gold  Medal 
for  Hourly  Recording  and  other  Registering  Thermometers. 


1. — Enamelling  the  centre  or  back  of  Thermometer  Tubes.  By  this  invention,  Negretti 
and  Zambra  have  been  enabled  to  make  Thermometers  at  least  twenty  times 
more  sensitive  than  heretofore.  The  delicate  Clinical  Thermometers  now  so 
extensively  used  could  never  have  been  efficiently  constructed  without  the  aid 
of  the  enamelled  tube.  See  Sensitive  Thermometers,  pages  32  and  160. 

2. — Negretti  and  Zambra's  Patent  Self-Registering  Maximum  Thermometer.  Pp.  36 
to  45.  For  a  Report  on  the  value  of  this  Thermometer  by  the  Kew  Committee 
see  pages  37  and  38. 

3. — The  Application  of  Porcelain  and  Enamelled  White  Glass  Scales  to  Barometers 
and  Thermometers,  the  divisions  being  permanently  etclied  or  painted  thereon ; 
a  plan  now  universally  adopted  by  all  makers. 

4. — Negretti  and  Zambra's  Patent  Mercurial  Minimum  Thermometers  (two  patents). 
See  pages  47  to  50. 

5. — Negretti  and  Zambra's  Patent  Self -Registering  Maximum  Thermometer,  specially 
arranged  for  obtaining  underground  temperatures,  Mines,  Springs,  &c.,  Marine 
service,  Solar  Observations,  &c.,  &c.  Seepages  42,  44,  145,  171,  and  172. 

6. — FitzRoy's  Marine  Gun  Barometer,  constructed  for  use  in  Her  Majesty's  Navy,  by 
Negretti  and  Zambra,  the  only  one  adopted  and  in  use  in  Her  Majesty's  vessels. 
See  pages  11  and  12. 

7. — FitzRoy's  Storm  or  Life-Boat  Service  Barometer.     See  page  143. 

8. — Pocket  and  Watch- sized  Aneroid  Barometer.  The  first  Pocket  Aneroid  ever  produced 
was  manufactured  by  Negretti  and  Zambra  for  the  late  Admiral  FitzRoy. 
See  pages  24  to  27. 

9. — The  Double  Bulb  Deep  Sea  Thermometer,  first  constructed  and  supplied  to  Her 
Majesty's  Navy  by  Negretti  and  Zambra  in  1 862.  For  full  particulars  and  the 
history  of  this  important  invention  see  pages  63,  64,  65,  and  173. 

10. — Improved  Standard  Mercurial  Deep-Sea  Thermometer,  the  only  Instrument  capable 
of  giving  correct  temperatures  of  the  bottom  or  any  intermediate  depth  of  the 
sea.  See  pages  66  and  67. 

11-— Negretti  and  Zambra's  Patent  Strengthened  Glass  Hydrometer.     Seepage  194. 
12.— A  Portable  form  of  the  Open  Range  Glycerine  Barometer.     See  page  18. 

13. — Self  Recording  Aneroid  Barometers  with  various  Improvements. 

See  pages  27  and  28. 

14.— Improved  Self-Recording  Barographs,  Thermographs,  Hygrometers. 

Seepages  30,  53  to  56, 130. 

15-— Negretti  and  Zambra's  Patent  Apparatus  for  recording  Hourly  Temperatures. 

Seepages  55  and  78. 

16.— Recording  Anemometers,  Electrical.  Various  arrangements  constructed  by 
Negretti  and  Zambra. 



Preface v.  to  vii 

Standard  Meteorological  Instruments  and  Meteorological  Publications      .         .  1  to  133 
Barometers,  Aneroids,  Thermometers,  and  Hygrometers      .        .        .    134  to  151,  152  to  175 

Hydrometers  and  Saccharometers 176  to  195 

Steam,  Vacuum,  Hydraulic,  and  Gas  Pressure  Gauges,  and  Counting  Machines  198  to  210 

Surveying  Instruments,  Land  Chains,  Measures,  &c 283  to  307 

Nautical  Instruments,  Sextants,   Quadrants,   Ships'  Lamps,  Logs,   Mariners' 

Compasses,  &c.,  and  Sun  Dials 308  to  327 

Mathematical  Drawing  Instruments,  Scales  and  Rules 330  to  349 

Globes  and  Orreries 328  to  329 

Spectacles,  Pocket  and  Hand  Magnifiers 213  to  224 

Various  Optical  Instruments 225  to  228 

Opera,  Race,  and  Field  Glasses *234  to  240 

Microscopes  and  Apparatus 256  to  275 

Telescopes 241  to  255 

Polarising  Apparatus 277  to  280 

Stereoscopes  and  Slides         .        .        . 229  to  233 

Magic  Lanterns  and  Dissolving  View  Apparatus 350  to  374 

Spectrum  Apparatus,  and  the  Radiometer 276,  281,  282 

Chemical  Apparatus,  of  Glass,  Porcelain,  and  Earthenware        ....  375  to  394 

Apparatus  for  Organic  Analysis 394,  395 

Chemical  and  Philosophical  Apparatus  and  Instruments,  of  Metal,  &c.      .        .  396  to  410 

Chemical  Cabinets  and  Portable  Laboratories 410,411 

Frictional  Electrical  Apparatus 412  to  427 

Voltaic  or  Galvanic  Apparatus 428  to  436 

Electro-Metallurgical  Apparatus 440  to  442 

Magnetic  and  Electro-Magnetic  Apparatus 443  to  449 

Electric  Bells  and  Alarms 459  to  467 

Electric  Light  Apparatus 437  to  439 

Thevmo-Electric  Apparatus 450' 

Induction  Coils  and  Apparatus 451  to  455 

Medical  Galvanic  and  Magnetic  Apparatus 455  to  459 

Pneumatic  Apparatus 468  to  476 

Hydrostatics  and  Hydraulics 477  to  480 

Photometers 497 

Acoustic  Instruments,  &c 494 

Mechanics  and  Dynamics 491  to  495 

Models  of  Steam  Engines,  &c.,  Apparatus  for  Illustrating  the  Phenomena  of  Heat  481  to  490 

Portable  Steam  Engines )          ....  211 

Gun  Metal  Fittings,  for  Steam  Engines  and  Boilers,  &c.   '          ....  210 

Bourdon's  Steam  Gauges 205  to  210 

Telegraph  Instruments  and  Apparatus 449,  461,  466 

Surgical  and  Medical  Instruments,  &c. 498  to  503 

Soda  Water  Machinery  and  Diving  Apparatus,  and  Ice  Machines      .        .        .  504  to  508 

Hydraulic  Machinery 509 

Gas  Motors 510,  511 

Photographic  Apparatus 517  to  553 

Appendix 554 

General  Reference  Index 567 

Mineralogical  and  Geological  Collections    .                 503 


IN  again  submitting  to  our  numerous  friends  and  patrons  a  greatly  enlarged 
and  revised  edition  of  our  Encyclopaedic  Catalogue,  we  do  so  with  some  decree 
of  pride, — firstly,  that  all  previous  editions  have  been  such  as  to  command  the 
extensive  patronage  bestowed  upon  them ;  and,  secondly,  from  the  award  made 
known  at  the  "  Great  International  Exhibition  at  Paris,"  that  the  superiority 
and  excellence  of  our  instruments,  which  gained  for  us  the  only  Prize  Medal  in 
1851,  is  still  maintained,  and  manifested  by  the  fact  that  at  Paris  in  1873  we  had 
awarded  to  us  the  ONLY  GOLD  MEDAL  given  for  our  class  of  instruments 
in  the  British  Section. 

This  is  further  confirmed  by  the  award  of  THREE  GOLD  MEDJLL>,  SILVER, 
and  BRONZE  MEDALS  at  the  International  Exhibitions,  London,  1883-1884, 
and  other  awards  specified  on  page  iii. 

In  this  edition,  as  in  all  that  have  preceded  it,  our  endeavour  has  been  to 
make  the  the  work,  not  merely  a  list  of  prices,  but  in  reality  a  guide  for  those 
who  are  purchasing  Scientific  Instruments  and  Apparatus  generally.  All 
instruments  are  well  described,  some  more  fully  than  others,  depending  upon 
the  importance  of  the  apparatus  or  article  under  consideration. 

Our  Meteorological  Instruments  we  particularly  recommend  to  those  who 
are  about  to  commence  making  observations  in  the  science  of  Meteorologv  as 
being  the  most  recently  improved  and  reliable  that  can  possibly  be  produced. 
In  confirmation  of  this  we  have  only  to  state  that  for  nearly  forty  years  our 
firm  have  had  the  honour  of  supplying  Standard  Instruments  to  all  the  most 
important  Meteorological  Observatories,  Scientific  Institutions,  and  Govern- 
ments of  the  World ;  most  of  the  Geographical  and  Deep  Sea  Exploring 
Expeditions  of  the  last  thirty  years  have  been  supplied  with  our  Instruments. 

To  enumerate  our  various  inventions  and  improvements  here  would  be, 
with  few  exceptions,  to  repeat  all  that  has  been  said  in  previous  editions ;  as 
it  would  be  tedious,  we  specify  these  Inventions  and  Improvements  on  pao-e  iv., 
and  indicate  the  section  or  page  in  the  Catalogue  where  they  will  be  found 
fully  described.  Our  doing  so  must  not  be  taken  as  an  act  of  egotism  ;  but  for 
the  special  purpose  of  placing  on  record  that  we  are  the  Inventors  and 
Improvers  of  such  instruments,  as  many  of  our  inventions  have  been 
appropriated  by  manufacturers,  and  sold  without  the  slightest  acknowledgment 
of  their  origin. 

Our  extensive  business  knowledge  and  experience  in  each  of  the  various 
sections  of  our  Trade  enables  us  to  obtain  full  and  correct  information  respecting 
any  new  Instruments  or  Inventions  :  hence  we  are  in  a  position  to  supply  to 
our  Correspondents  any  Specialities  made  and  sold  by  other  firms  at  their 
advertised  or  Catalogue  prices. 


At  page  v.  will  be  found  a  Table  of  Contents,  referring  to  the  pages  where 
any  particular  section  or  class  of  apparatus  will  be  found,  and  at  page  567  an 
extensive  general  Index,  giving  the  marginal  number  or  page  for  each 
Instrument:  these,  combined  with  upwards  of  Thirteen  Hundred  "Wood 
Engravings  (a  large  proportion  of  them  new),  will  assist  the  reader  in  searching 
for  any  particular  item. 

When  Orders  are  transmitted  in  Foreign  Languages,  N".  &  Z.  advise 
their  friends  to  send  verbatim  copies  of  such  orders  in  the  original  language, 
as  it  often  occurs  that  where  the  order  has  been  translated  and  copied  by 
persons  unacquainted  with  the  nature  or  use  of  the  articles  written  for,  serious 
errors  arise  in  the  carrying  out  their  correspondents'  commands. 

Correspondents  may,  if  preferable  to  them,  write  in  French,  Italian, 
Spanish,  or  German. 

A  liberal  commission  allowed  to  Merchants,  Shippers,  or  Agents  on  large 
transactions.  Merchants  favouring  us  with  copies  of  their  clients'  orders  will 
have  special  quotations  furnished  to  them  if  desired. 

Full  and  explicit  instructions  should  accompany  orders  as  to  the  Address, 
mode  of  Conveyance,  Shipment,  Insurance,  Consular  Forms,  and  Declarations, 
etc.,  etc.  Foreign  or  Country  orders  must  be  accompanied  by  an  adequate 
Remittance  or  Order  for  Payment,  or  Satisfactory  Reference  in  London. 

Every  possible  care  being  taken  in  packing  Apparatus  and  Instruments  to 
insure  safety  in  carriage,  ibe  cannot  be  responsible  for  any  damage  that  may  occur 
in  transit  after  the  goods  leave  our  establishment. 

The  probable  expense  of  Packing  Cases,  Tin  or  Zinc-lined,  may  be  taken 
at  say  from  5  to  10  per  cent,  on  the  value  of  articles  of  ordinary  dimensions 
and  weight.  Yery  bulky  or  extremely  heavy  goods  can.  hardly  be  estimated 
for ;  but  1ST.  &  Z.  will  undertake  that  all  packages,  &c.,  shall  be  supplied  at 
the  lowest  possible  net  charge. 

All  communications  from  abroad  should  be  directed  to  the  Chier 
Establishment,  Negretti  &  Zambra,  Holborn  Viaduct,  E.G.,  London. 
Letters  for  their  Branches  to  be  specially  addressed  45,  Cornhill,  E.G. ; 
122,  Regent  Street,  W.  ;  or,  Negretti  &  Zambra's  Photographic 
Department,  Crystal  Palace,  Sydenham,  S.E. 

The  compilation  and  revision  of  this  New  Edition  of  our  Catalogue  has 
again  been  entrusted  by  us  to  Mr.  R.  WILLATS,  the  Manager  of  our  retail 
department  at  Holborn  Viaduct ;  and  we  hope  that  both  as  a  Price  List  and  a 
Book  of  Reference  it  will  be  found  much  superior  to  its  predecessors. 




7     Last  line  0'45  should  read  0'6. 
20    Fig.  21.     Price  should  read  £27   !<»-. 
27    Last  line,  18s.,  should  read  15s. 
32    No.  39.     For  T\jth  of  degree  read  ^ths. 
58    Last  line,  20s.,  should  read  7s. 

(This  instrument  has  been  considerably  improved  since  catalogue  was  printed. 

Full  particulars  forwarded  on  application.) 
65    The  line  "1  Cubic  Foot  of  Sea  Water"  should  read  "Fresh   Water"  (see 

page  558). 

67    Price  of  Magnaghi  Pattern  Deep  Sea  Thermometer,  £5  10s. 
75    No.  98.    63s.  should  read  50s. 

94    No.  133  is  no  longer  made,  having  been  superseded  by  No.  132. 
102    No.  144.    4-inch  Anemometer,  63s.  should  read  60s. 
114    No.  158  is  no  longer  made. 
124    No.  1  Set  of  Instruments,  instead  of  £330  to  £450,  read  £170  to  £250. 

131  Dip  Circle  No.  136.    £35  should  read  £40. 

132  Prices  of  Charts  for  figures  21  and  29.     25s.  should  read  21s. 
For  fig.  28  read  15s. 

For  Anemometers  and  Tide  Gauges  read  35s. 

133  Negretti  and  Zambra's  Treatise  and  Ksemtz's  Meteorology  are  both  out  of 


143    No.  171.    FitzRoy  Barometer,  £6  10s.,  should  read  £6  6s. 
14§    Fig.  182  should  read  183. 

Fig.  183  should  read  182. 
149    No.  199  can  also  be  supplied  at  £5  5s. 
157    No.  267     14-inch,  10s.,  should  read  8s.  6d. 
159    No.  299.     400°  should  read  140?. 

No.  300.    600°  should  read  212°. 

No.  301  should  read  to  600°. 

162  The  Thermometers,  Nos.  313,  314,  and  315,  are  not  to  be  recommended,  and 

are  superseded  by  Nos.  316  and  317. 

163  No.  316  are  also  supplied  on  Boxwood  Scales  at  5s.  6d.  and  7s.  6d. 
Porcelain  Scale  in  Japanned  Metal  Case,  10s.  6d.  should  read  7s.  6d. 
No.  317.    12s.  6d,  should  read  10s.  6d. 

No.  321.  10s.  6d.  should  read  7s.  6d. 

No.  322.  12s.  6d.  should  read  10s.  6d. 

168  No.  366.  16s.  6d.  should  read  15s. 

169  No.  386.  130°  should  read  110°. 
177    No.  423.  27s.  6d.  should  read  21s. 
186    No.  485.  16s.  6s.  should  read  12s.  6d. 

No.  486.     10s.  6d.  should  read  7s.  6d. 
188    No.  510  is  no  longer  made. 

No.  514.    Fig.  466  should  read  514. 

No.  515.     Fig.  467  should  read  515. 

No.  517.    Fig.  469  should  read  517. 
196    No.  559.     "  Vacuum  Gauge  "  should  read  "  Pressure  Gauge." 

Fig.  459  should  read  559. 
199  Fig.  578  should  read  587. 
201  Fig.  A  should  read  C. 

Fig.  C  should  read  A. 

Small  Machine  Counter  "  with  4  figures  at  63s."  should  read  "  with  6  figures 
and  reciprocating." 



223  Fig.  697  should  read  679. 

226  Fig  40  should  read  740. 

250  No.  859,  referred  to  as  fig.  859,  should  read  fig.  861. 

251  No  861  should  read  859. 

252  No.  864.    For  190  diameters  read  100. 

253  No.  866.    £8  8s,  should  read  £S. 

254  No.  868.    £8  8s.  should  read  £8. 
No.  871.    £14  should  read  £14  10s. 

£200  should  read  £190. 
£300  should  read  £280. 
„  £400  should  read  £390. 

268    No.  925.    ith  Object  Glass  £4  10s.,  should  read  £6  10s. 

ith        ditto         £5  should  read  £7  10s. 
272    No.  995    6s.  should  read  5s. 
275    No.  1042.    £8  8s.  should  read  £7  7s. 
No.  1044.    10s.  6d.  should  read  6s.  6d. 
No.  1045.    12s.  6d.  should  read  8s.  6d. 
280    No.  1075  are  also  supplied  at  5s.  and  7s,  6 d. 
285    No.  1115.    20  seconds  should  read  30. 

291  No.  1155.    £18  18s.  should  read  £19  10s. 

292  No.  1165.    36s.  should  read  35s. 

297  No.  1186.    £3  3s.  should  read  £3  10s. 

307  30-inch  Pentagraph,  £10  10s.,  should  read  £9  10s. 

308  No.  1293.    5-inch  should  read  6-inch. 
317  No.  1345.    £3  3s.  should  read  £2  2s. 
325  No.  1404.    5s.  should  read  3s. 

No.  1407.    Is.  should  read  Is.  9d. 
No.  1418.    Is.  should  read  Is.  6d. 
356    No.  1761.    £12  12s.  should  read  £10  10s. 

397  No.  2167.*  16s.  should  read  10s.  6d. 

398  No.  2181  is  no  longer  made. 

412    No.  2380.    9-inch  at  63s.  should  read  10-inch 

432    Fig.  1888  should  read  2564. 

434    No.  2554.    No.  1  size,  5s.  6d.  should  read  4s.  6d. 

No.  2  size,  4s.,  should  read  3s.  6d. 
„  No.  3  size,  3s.  6d.,  should  read  3s. 

No.  2604  has  now  been  superseded  by  machines  of  improved  construction. 

447  Fig.  2079  should  read  2709. 

448  No.  2709  is  no  longer  made. 
458    No.  2784.    32s.  should  read  30s. 

477  No.  2912.    Fig  2612  should  read  2912. 

479  Fig.  9240  should  read  2940. 

481  Fig.  2995  should  read  2955. 

483  No.  2951.    Fig.  2251  should  read  2951. 

No.  2954.    No.  2144  should  read  fig.  3044. 

490  No.  3009.    Figs.  2109  and  2109*  should  read  figs.  3009  and  3009*, 

493  Fig.  2694  should  read  3042. 

517  No.  3159.    For  £  plate  at  £3  3s.  read  \  plate. 

545  No.  3282.    £5  15s.  should  read  £6  5s. 




THE  practical  usefulness  of  Meteorological  Instruments  as  weather  indicators, 
and  their  increasing  employment  for  Scientific  and  Sanitary  investigation, 
render  a  knowledge  of  their  construction  and  principles  desirable  to  all. 
Impressed  with  the  idea  that  we  shall  be  supplying  a  want,  in  giving  simple 
descriptions  of  those  now  in  use,  we  have  endeavoured  to  condense  such 
information  regarding  the  instruments  used  in  Meteorology  in  the  present 
section  of  our  Catalogue. 

Every  Meteorological  Instrument  of  any  practical  value  being  described, 
with  plain  instructions  for  using  them,  purchasers  will  be  enabled  to  select 
such  as  seem  to  them  most  suited  to  their  requirements. 

For  convenience  of  reference  and  comparison  we  arrange  and  describe  the 
different  instruments  used  for  Meteorological  observation  under  the  following 
headings,  viz.  :  Instruments  to  show,  1st,  the  pressure  of  the  atmosphere;  2nd, 
the  temperature  of  the  air  ;  3rd,  the  absorption  and  radiation  of  the  sun's  heat 
by  the  earth's  surface ;  4th,  the  humidity  of  the  air  ;  5th,  the  amount  and 
duration  of  rainfall ;  6th,  the  direction,  the  horizontal  pressure,  and  the  velocity 
of  winds  ;  7th,  the  electric  condition  of  the  atmosphere,  the  prevalence  and 
activity  of  ozone,  magnetic,  and  tidal  phenomena,  &c.,  &c. 




1.  Principle  of  the  Barometer.— The  first  instrument  which  gave  the  exact 
measure  of  the  pressure  of  the  atmosphere  was  invented  by  Torricelli,  a  Florentine 
pupil  of  Galileo,  in  1643.  It  is  constructed 
as  follows  :  A  glass  tube,  C  D  (fig.  1),  about 
34  inches  long,  and  from  two  to  four-tenths 
of  an  inch  in  diameter  of  bore,  having  one 
end  dosed,  is  filled  with  mercury.  In  a 
cup,  B,  a  quantity  of  mercury  is  also  poured. 
Then,  placing  a  finger  securely  over  the 
open  end,  C,  invert  the  tube  vertically  over 
the  cup,  and  remove  the  finger  when  the 
end  of  the  tube  dips  into  the  mercury.  The 
mercury  in  the  tube  then  partly  falls  out, 
bat  a  column,  A  B,  about  30  inches  in 
height,  remains  supported.  This  column  is 
a  weight  of  mercury,  the  pressure  of  which 
upon  the  surface  of  that  in  the  cup  is  pre- 
cisely equivalent  to  the  corresponding  pres- 
sure of  the  atmosphere.  As  the  atmospheric 
pressure  varies,  the  length  of  this  mercurial 
column  also  changes.  It  is  by  no  means 
constant  in  its  height ;  in  fact,  it  is  very 
seldom  stationary,  but  is  constantly  rising  or  falling  in  the  tube.  It  is,  there- 
fore, an  instrument  by  which  the  fluctuations  taking  place  in  the  pressure  of 
the  atmosphere,  arising  from  changes  in  its  weight  and  elasticity,  can  be  shown 
and  measured.  It  has  obtained  the  name  Barometer,  or  measurer  of  heaviness, 
— a  word  certainly  not  happily  expressive  of  the  utility  of  the  invention.  If 
the  bore  of  the  barometer  tube  be  uniform  throughout  its  length,  and  have  its 
sectional  area  equal  to  a  square  inch,  it  is  evident  that  the  length  of  the  column, 
which  is  supported  by  the  pressure  of  the  air,  expresses  the  number  of  cubic 
inches  of  mercury  which  compose  it.  The  weight  of  this  mercury,  therefore, 
represents  the  statical  pressure  of  the  atmosphere  upon  a  square  inch  of 

In  England  the  annual  mean  height  of  the  barometric  column,  reduced  to 
the  sea-level,  and  to  the  temperature  of  32°  Fahrenheit,  is  about  29'95  inches. 
A  cubic  inch  of  mercury  at  this  temperature  has  been  ascertained  to  weigh 
0-43967  Ibs.  avoirdupois.  Hence  29'95  xO'48967^14'67  Ibs.,  is  the  mean 


value  of  the  pressure  of  the  atmosphere  on  each  square  inch  of  surface,  near  the 
sea-level,  about  the  latitude  of  50  degrees.  Nearer  the  equator  this  mean 
pressure  is  somewhat  greater  ;  nearer  the  poles,  somewhat  less.  For  common 
practical  calculations  it  is  assumed  to  be  15  Ibs.  on  the  square  inch.  When  it 
became  apparent  that  the  movements  of  the  barometric  column  furnished  indi- 
cations of  the  probable  coming  "changes  in  the  weather,  an  attempt  was  made 
to  deduce  from  recorded  observations  the  barometric  height  corresponding  to 
the  most  notable  characteristics  of  weather.  It  was  found  that  for  fine  dry 
weather  the  mercury  in  the  barometer  at  the  sea-level  generally  stood  above  30 
inches  ;  changeable  weather  happened  when  it  ranged  from  30  to  29  inches, 
and  when  rainy  or  stormy  weather  occurred  it  was  even  lower.  Thus,  it  became 
the  practice  to  place  upon  barometer  scales  words  (Fair,  Change,  Rain,  &c.), 
indicatory  of  the  weather  likely  to  accompany,  or  follow,  the  movements  of  the 
mercury ;  and  the  instruments  bearing  them  obtained  the  name  "  Weather 











































B   2 




FIG,  2. 



2.     Negretti  &  Zambra's  Standard  Barometers  are 

constructed  on  Fortin's  principle,*  which  has  been  proved 
to  be  the  most  reliable  and  convenient  arrangement 
yefc  introduced.  The  level  of  the  mercury  in  the  cistern 
being  adjusted  previous  to  each  observation  to  a  fixed 
zero  point  of  ivory,  loss  of  mercury  from  leakage  or 
oxidation  is  of  little  or  no  importance,  and  does  not 
affect  the  accuracy  of  the  readings  of  the  instrument. 
The  tubes  are  of  varying  internal  diameter,  according 
to  the  price  of  each  barometer.  These  tubes  are  filled 
with  pure  mercury,  very  carefully  boiled  in  the  tube  to 
perfectly  expel  all  air  or  moisture. 

The  barometer  tube  is  mounted  in  a  brass  tubular 
frame,  extending  throughout  its  whole  length ;  the 
upper  portion  of  it  has  two  longitudinal  openings  5 
on  one  side  of  the  front  opening  is  the  barometrical 
scale  of  English  inches,  divided  to  show,  by  means  of  a 
vernier,  -^oth  of  an  inch ;  on  the  opposite  side  is  some, 
times  divided  a  scale  of  French  millimetres,  reading 
also  by  a  vernier  to  y^th  of  a  millimetre.  The  reservoir 
or  cistern  of  the  barometer  is  of  glass,  closed  at  bottom 
by  means  of  a  leather  bag,  acted  upon  by  a  thumb-screw 
passing  through  the  bottom  of  an  arrangement  of  brass- 
work,  by  which  it  is  protected.  A  delicate  thermometer 
with  the  scale  divided  on  its  stem,  so  arranged  as  to 
give  as  accurately  as  possible  the  temperatures  of  the 
column  of  mercury,  is  attached  to  the  brass  tube.  A 
mahogany  board,  with  brass  bracket  and  ring,  with 
three  adjusting  screws  for  suspending  and  adjusting 
the  barometer,  is  supplied  with  each  instrument. 

*  This  form  of  barometer,  now  universally  adopted  by  all  makers,  was 
originally  introduced  by  Negretti  and  Zambra. 

45,    CORNHILL,    E.G.,    AND    122,    "REGENT   STREET,    W.,    LONDON. 

Fortin's  barometer  cistern  shown  in  section  by  fig.  3,  is 
formed  of  a  glass  cylinder,  which  allows  of  the  level  of  the 
mercury  within  being  seen.  The  bottom  of  the  cylinder  is 
made  of  flexible  leather,  like  a  bag,  so  as  to  allow  of  being 
pushed  up  or  lowered  by  means  of  a  screw,  D  B,  worked  from 
beneath.  This  screw  moves  through  the  bottom  of  a  brass 
cylinder,  C  C,  which  is  fixed  outside,  and  protects  the  glass 
cylinder  containing  the  mercury.  At  the  top  of  the  interior 
of  the  cistern  is  fixed  a  small  piece  of  ivory,  .A,  the  point  of 
which  exactly  coincides  with  the  zero  of  the  scale.  This 

screw    and  moveable    cistern-bottom        FIG.  3. 

serve  also  to  render  the  barometer  portable,  by  con- 

fining  the  mercury  in  the  tube,  and  preventing  its 

descending  into  the  cistern. 

Fig.  4  exhibits  the  external  construction  of  the 
cistern  portion  of  a  standard  barometer.  S  S  are 
metal  screws  that  secure  the  glass  cylinder  or  cistern 
G  Gr  partly  filled  with  mercury,  M,  through  this  the 
tube  T  passes  down  into  the  flexible  leather  bag,  with 
which  the  instrument  is  adjusted  or  made  portable 
by  the  screw,  D  B,  as  previously  described.  At  P  is 
shown  the  white  ivory  zero  point  to  which  the  level  of 
the  mercury  in  the  glass  cistern  is  always  corrected 
previous  to  reading  off  the  height  of  the  mercurial 
column.  This  ivory  point  is  seen  at  A  in  the  section 
FIG.  4.  fio-  3,  and  at  P  in  fig.  4. 

Directions  for  fixing  Hie  Barometer. — In  selecting  a  position  for  a  barometer 
care  should  be  taken  to  place  it  so  that  the  sun  cannot  shine  upon  it,  and  that 
it  is  not  affected  by  direct  heat  from  a  fire.  The  cistern  should  be  from  two  to 
three  feet  above  the  ground,  which  will  give  a  height  for  observing  convenient 
to  most  persons.  Having  determined  upon  the  position  in  which  to  place  the 
instrument,  fix  the  mahogany  board  as  nearly  vertical  as  possible ;  and  ascer- 
tain if  the  barometer  is  perfectly  free  from  air,  in  the  following  manner  : — lower 
the  adjusting  screw  at  the  bottom  of  the  cistern  several  turns,  so  that  the 
mercury  in  the  tube,  when  held  upright,  may  fall  two  or  three  inches  from  the 
top  ;  then  slightly  incline  the  instrument  from  the  vertical  position,  and  if  the 
mercury  in  striking  the  top  elicit  a  sharp  tap,  the  instrument  is  perfect.  If  the 
tap  be  dull,  or  not  heard  at  all,  there  is  air  above  the  mercury  ;  this  must  be 
driven  into  the  cistern  by  partially  rescrewing  and  then  inverting  the  instrument, 
and  gently  tapping  it  with  the  hand.  The  barometer  being  in  perfect  condition, 


suspend  it  on  the  brass  bracket,  its  cistern  passing  through  the  ring  at  bottom, 
and  allow  it  to  find  its  vertical  position  ;  after  which  firmly  clamp  it  by  means 
of  the  three  clamping  screws. 

Directions  for  taking  an  Observation. — Having 
taken  the  temperature  by  the  attached  thermometer, 
the  mercury  in  the  cistern  must  be  raised  or  lowered 
by  means  of  the  thumb-screw  (s),  fig.  2,  until  the 
ivory  point  (E),  and  its  reflected  image  in  the  mer- 
cury (D),  are  just  in  contact ;  the  vernier  is  then 
moved  by  means  of  the  milled  head,  until  its  lower 
edge  just  excludes  the  light  from  the  middle  and 
uppermost  point  of  the  mercurial  column  as  seen  in 
fig.  5  ;  the  reading  is  then  taken  by  means  of  the 
scale  on  the  limb  and  the  vernier.  In  observing,  the 
eye  should  be  placed  in  a  right  line  with  the  fore  and 
back  edges  of  the  lower  termination  or  edge  of  the 
vernier.  A  small  white  reflector  placed  behind  the 
barometer  will  assist  in  throwing  the  light  through 
the  brass  frame  and  the  glass  tube  ;  and  the  observer's 
vision  may  be  further  assisted  by  the  use  of  a 
magnifying  lens.  The  great  object  in  standard 
barometers,  is  to  obtain  exact  readings,  which  can  only  be  done  by  having  the 
eye,  the  front  of  the  zero  edge  of  the  vernier,  the  top  of  the  mercurial  column, 
and  the  back  of  the  vernier,  in  the  same  horizontal  plane. 

To  remove  the  Instrument. — If  it  should  be  necessary  to  remove  the 
barometer,  first,  by  means  of  the  adjusting  screw  (s),  fig.  2,  drive  the  mercury  to 
the  top  of  the  tube,  turning  the  screw  gently  when  the  mercury  approaches  the 
top,  and  stop  turning  directly  any  resistance  is  experienced  ;  next  remove  the 
instrument  from  the  bracket,  slowly  invert  it,  and  in  carrying  keep  the  cistern 
end  uppermost. 

3.  The  Barometer  Vernier. — The  Vernier,  an  invaluable  contrivance 
for  measuring  small  spaces,  was  invented  by  Peter  Vernier,  about  the  year 
1630.  The  barometer  scale  is  divided  into  inches  and  tenths.  The  vernier 
enables  us  to  accurately  sub-divide  the  tenths  into  hundredths,  and,  even  to 
thousandths  of  an  inch.  It  consists  of  a  short  scale  made  to  pass  along  the 
graduated  fixed  scale  by  a  sliding  or  rack-and-pinion  adjustment. 

The  scales  of  standard  barometers  are  usually  divided  into  half-tenths,  or 
•05,  of  an  inch,  as  represented,  in  fig  6,  by  AB.  The  vernier,  C  D,  is  made  equal 
in  length  to  twenty-four  of  these  divisions,  and  divided  into  twenty-five  equal 
parts  ;  consequently  one  space  on  the  scale  is  larger  than  one  on  the  vernier,  by 
the  twenty-fifth  part  of  *05,  which  is  '002  inch,  so  that  such  a  vernier  shows 

FIG  5. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 






differences  of  "002  inch.  The  vernier  of  the  figure  reading  upwards,  the  lower 
edge,  D,  will  denote  the  top  of  the  mercurial  column  ;  and  is  the  zero  of  the 
vernier  scale.  In  fig.  6,  the  zero  being  in  line  exactly  with  29  inches  and  five- 
tenths  of  the  fixed  scale,  the  barometer  reading  would  be  29*500  inches.  It  will 
be  seen  that  the  vernier  line,  a,  falls  short  of  ^ 

a  division  of  the  scale  by,  as  we  have  ex- 
plained, -002  inch  ;  6,  by  '004  ;  c,  by  '006  ; 
d,  by  "008 ;  and  the  next  line  by  one  hun- 
dredth. If,  then,  the  vernier  be  moved  so  as 
to  make  a  coincide  with  z,  on  the  scale,  it 
will  have  moved  through  '002  inch  ;  and  if 
1  on  the  vernier  be  moved  into  line  with  y 
on  the  scale,  the  space  measured  will  be1 010. 
Thus,  the  figures  1,  2,  3,  4,  5  on  the  vernier 
measure  hundredths,  and  the  intermediate 
lines  even  thousandths  of  an  inch.  In  fig  6*, 
the  zero  of  the  vernier  is  between  29'65  and 
2970  on  the  scale.  Passing  the  eye  up  the 
vernier  and  scale,  the  second  line  above  3  is 
perceived  to  lie  evenly  with  a  line  of  the 
scale.  This  gives  '03  and  '004  to  add  to 
29*65,  so  that  the  actual  reading  is  29'684 

For    the     ordinary     purposes    of   the 





barometer  as  a  "  weather  glass,"  such 
minute  measurement  is  not  required.  In 
household  and  marine  barometers,  the  scale 
is  only  divided  to  tenths,  and  the  vernier 
constructed  to  measure  hundredths  of  an  inch. 
This  is  done  by  making  the  vernier  either  9 





'1  5 























FIG  6*. 

or  ll-10ths  of  an  inch  long,  and  dividing  it  into  ten  equal  parts.  The  lines 
above  the  zero  line  are  then  numbered  from  1  to  10 ;  sometimes  the  alternate 
divisions  only  are  numbered,  the  intermediate  numbers  being  very  readily 
inferred.  Hence,  if  the  first  line  of  the  vernier  agrees  with  1  on  the  scale,  the 
next  must  be  out  one-tenth  of  a  tenth,  or  '01  of  an  inch  from  agreement  with 
next  scale  line  ;  the  following  vernier  line  must  be  "02  out,  and  so  on.  Conse- 
quently, when  the  vernier  is  set  to  the  mercurial  column,  the  difference  shown 
by  the  vernier  from  the  tenth  on  the  scale  is  the  hundredths  to  be  added  to  the 
inches  and  tenths  of  the  scale. 

Price,  Standard  Barometer  (fig  2) £880 

Ditto,  with  English  and  Millimetre  Scales       990      10  10    0 
Ditto,  with  Tube  0'45-inch  internal  diameter      .  12  12    0 



FIG.  9. 

FIG.  7.  FIG.  8. 

4.  Large   Standard  Barometers   with   attached  Thermometer  suited 
for   Observatories   and  Public  Institutions.      The    tubes    are    T6oths    internal 
diameter,  and  the  bulbs  of  the  thermometers  are  of  the  same  dimensions. 

Price,  Fig.  7.     £21     0     0 

5.  Observatory   Standard    Barometers   with   extra   large  tube    and 
cistern,  arranged  for  observations  being  taken  by  the  Cathetometer  for  extreme 
precision,  as  used  at  the  Greenwich  and  Kew  Observatories. 

Price,  Barometer,  Fig.  8,       ,        £25    0    0        £30    0    0 
Cathetometer,  Fig.  9          ...        £35    0    0 

45,   CORNHILL,   E.G.,  AND    122,    BEGENT   STREET,   W.,    LONDON. 

FIG.   10. 

FIG.  11. 

6.  Cathetometer,^  (fig.  10.)  Improved  arrangement,  suited  for 
Observing  Stations  of  the  First  Class.  Price  £50  to  £80 ;  varying  with  the 
fineness  and  accuracy  of  the  divisions  and  the  number  of  adjustments  attached 
to  the  instrument. 


7.  Observatory  Standard  Barometer,  fig.  11,  of  the  highest  class 
suitably   mounted,  for   being  read  off    with  the  Cathetometer,   with    a   tube 
of  exceedingly   large   internal   diameter,  the  cistern  also   being  of  very  large 
area — especially   arranged   for  taking  observations    with    the    most   extreme 
precision.     Our  woodcut  shows  the  Barometer   to  be  without  any   scale,  the 
readings  being  obtained  by  observing  the  level  of  the  mercury  in  the  tubes 
and  the  upper  point  of  the  cistern  index,  (or  zero  screw)  through  the  telescope 
of  the  Cathetometer.  Price,  as  fig.  11,  £50    0    0  to  70    0    0 

8.  The  Cathetometer,  shown  in  fig.  9,  is  used  for  ascertaining  with 
the  utmost  accuracy  the  space  or  distance  between  any  two  points.     A  brass  rod 
or  cylinder  is  firmly  supported  on  a  heavy  base  having  three   arms,  each    arm 
furnished  with  adjusting  screws  for  setting   the  upright  rod    truly  vertical. 
This  rod  is  accurately  divided  throughout  its  length,  and  so  arranged  that  it 
will  revolve  horizontally. 

Exactly  at  right  angles  to  this  scale  and  attached  to  it  is  a  framework 
carrying  a  small  Achromatic  Telescope  furnished  with  fine  wire  or  spider  lines 
in  the  eye-piece.  This  telescope  is  mounted  with  levels,  having  coarse  and  fine 
adjustments  with  clamps,  &c.,  much'  in  the  same  manner  as  a  Theodolite 
Telescope.  The  distance  between  the  points  to  be  ascertained  is  observed 
through  the  telescope,  which  can  be  moved  with  its  adjustments  vertically 
up  or  down  upon  the  divided  scale — and  its  indications  read  off  by  means 
of  verniers,  which  sub-divide  the  scale  to  the  five-hundredth  or  one-thousandth 
part  of  an  inch. 

The  Cathetometer  scale  may  be  divided  either  in  English  inches  or 
Centimetres  and  Millimetres  as  desired. 

Price  of  Cathetometer,  as  fig.  9,  £35    0    0 

9.  Glass  Cases  for  Standard  Barometers  of  polished  ebonized  wood 
with  plate  glass  sides  and  door  with  secure  fastenings  for  the    exclusion   of 
dust  and  preserving  the  instrument  from  injury.          .Price £5    5    0  to  £10    10    0 

10.  Testing  Chamber  with  double-action  Air  Pump  for  testing  Standard 
Barometers,  as  used  at  the  Kew  Observatory.  £70    0    0 

11.  Negretti  and  Zambra's  Mountain  Barometer  (fig.  12),  on  Fortin's 
principle,   is  more  portable,    and   less   liable    to    derangement   than    ordinary 
mountain  barometers.      The  arrangement  of  the  flexible  leather  cistern  is  so 
simple  that  should  the  mercury  become  oxidized,  it  can  be  quickly  removed, 
cleaned,  and  returned  to  the  cistern  without  fear  of  affecting  the  correctness 
of  the   indications.      The   vernier   reads   to   '002    of  an  inch,  and   the   whole 

45,    CORNHILL,    E.G.,   AND    122,    EEGENT   STEEET,   W.,   LONDON. 



FIG.  14. 

instrument  is  arranged  in  the  most  compact  and  convenient  form 
for    safety    in    travelling,   and   obtaining  very   accurate   altitude 


Price,  Including  Brass  Tripod  Stand  (as  fig.  12)  and  Travelling 
Case  for  the  Barometer,  with  English  or  Millimetre  Scale      £10  10    0 

12.  Standard  Mountain  Barometer  of  simpler  form  and 
smaller  tube.  Price  £8    8    0 

13.  Standard  Syphon  Barometer  (Gay  Lussac's),  divided 
on  the  glass  tube,  suited  for  Laboratory  use  (fig.  13),  mounted  on 
mahogany  board,  with  thermometer  and  two  verniers.   Price  £550 

14.  Standard  Syphon  Tube  Mountain  Barometer  (Gay 
Lussac's),  with   attached  thermometer,    and  improvement  in  the 
tube  for  excluding  air.     This  is  shown  in  fig.  14,  and  known  as 
Gay  Lussao's  Air  Trap :  its  use  being  to  arrest  any  air  that  may 
pass  up  between  the  glass  and  the  mercury.     The  bubbles  of  air 
are  stopped  and  collected  at  the  shoulder  of  the  trap  at  K,  and 
cannot  possibly  get  up  into  the  tube.     This  barometer  is  light  and 
convenient  for   travelling.     The  graduations   are  upon  the   brass 
tube  with  verniers  at  each  extremity  reading  from  the  centre.     By 
adding  the  two  readings  together  the  correct  height  of  column  is 
obtained  to  -g^th  °f  an  inch. 

Price  of  Barometer,   in  leather  travelling  case,  with   Brass 

Tripod  Stand  (fig.  15) £880 

This  Syphon  Barometer  does  not  require  correction  for  either 
capillarity  or  capacity,  as  each  surface  of  the  mercury  is  equally 
depressed  by  capillary  attraction,  and  the  quantity  of  mercury 
which  falls  from  the  long  limb  of  the  tube  occupies  the  same  length 
in  the  short  one.  The  barometric  height  must,  however,  be  cor- 
rected for  temperature,  as  in  the  cistern  barometer. 

15.  Board  of  Trade  Standard  or  Kew  Marine  Barometer, 
bronzed  brass  frame,  with  iron  cistern,  and  mounted  on  mahogany 
board,  as  in  fig.  16.     The  graduations  on  the  scale  are  so  arranged 
that  the  exact  reading  can  be  obtained  at  once,  without  any  previous 
adjustment  of  the  level  of  the  mercury  in  the  cistern,  as  in  the  Fortin 
barometer.  Price  £550 

16.  Meteorological  Station  Barometer,  Bronzed 
metal  frame,  with  iron  cistern  and  glass  scales  mounted  on  mahogany 
board.     Exact  readings  can  be  taken  without  any  previous  adjust- 
ment of  the  mercury,  fig.  17.  Price,  £770 

17.  Board    of    Trade     Marine   Barometer,    similar   to 
No.    16,   but   mounted   on  arm,  with  gymbal  ring,  instead  of    a 
mahogany  board.  Price,  Packed  in  travelling  case     .£440 


18.  FitzRoy's  Marine  Gun  Barometer,  constructed  by  Messrs. 
Negretti  &  Zambra  under  the  immediate  superintendence,  and  named  by  permission 
of,  the  Admiral  for  the  special  use  of  Her  Majesty's  navy,  mounted  with 
vulcanised  India-rubber  packing  to  prevent  concussion  and  breakage  caused 
by  gun-firing. 

Packed  in  case £5  10    0 

Extra  tube  for  ditto 1150 

See  also  Section  Marine  Barometers. 

Trials  of  the  FitzRoy  Marine  Barometer  under  Fire  of  Guns.— Some  of  the  first  baro- 
meters made  by  Messrs.  Negretti  and  Zanibra  on  Admiral  FitzRoy's  principle  were  severely  tried  under  the 
heaviest  naval  gun  firing,  on  board  H.  M.S.  Excellent',  and  under  all  the  circumstances  they  withstood  the 
concussion.  The  purpose  of  the  trials  was  "  to  ascertain  whether  the  vulcanised  India-rubber  packing  round 
the  glass  tube  of  a  new  marine  "barometer  did  check  the  vibration  caused  by  firing,  and  whether  guns 
might  be  fired  close  to  these  instruments  without  causing  injury  to  them."  In  the  first  and  second  series 
of  experiments,  a  marine  barometer  on  Admiral  FitzRoy's  plan  was  tried  against  a  marine  barometer 
on  the  Kew  principle,  both  instruments  being  new,  ani  treated  in  all  respects  similarly.  They  were 
"  hung  over  the  gun,  under  the  gun,  and  by  the  side  of  the  gun, — the  latter  both  inside  and  outside  a 
bulkhead ;  in  fact,  in  all  ways  that  they  would  be  tried  in  action  with  the  bulkheads  cleared  away."  The 
result  was  that  the  Kew  barometer  was  broken  and  rendered  useless,  while  the  new  pattern  barometer 
was  not  injured  in  the  least.  In  a  third  series  of  experiments,  Mr.  Negretti  being  present,  five  of  the 
new  pattern  barometers  were  subjected  to  the  concussion  produced  by  firing  a  63-pounder  gun  with  shot, 
and  IGlbs.  charge  of  powder.  They  were  suspended  from  a  beam  immediately  under  the  gun,  then  from  a 
beam  immediately  over  the  gun,  and  finally  they  were  suspended  by  the  arm  to  the  bulkhead,  at  the 
distance  of  only  3ft.  6in  from  the  axis  of  the  gun ;  and  the  result  was,  according  to  the  official  report, 
"that  all  these  barometers,  however  suspended,  would  stand,  without  the  slightest  injury,  the  most 
severe  concussion  that  they  would  ever  be  likely  to  experience  in  any  sea-going  man-of-war."  These  trials 
were  conducted  under  the  superintendence  of  Captain  Hewlett,  C.B.,  and  the  guns  were  fired  in  the 
course  of  his  usual  instructions.  His  reports  to  Admiral  FitzRoy,  giving  all  the  particulars  of  the  trials* 
are  published  in  the  "  Ninth  number  of  Meteorological  Papers,"  issued  by  the  Board  of  Trade.* 

*  With  reference  to  these  barometers,  we  have  received  the  subjoined  testimonial,  with  permission  to 
use  as  we  please. 

"  Meteorologic  Office,  June  12th,  1863. 

"  The  barometers  which  you  have  lately  supplied  to  Her  Majesty's  ships  through  this  Office  are 
much  approved,  being  good  for  general  service,  afloat  or  on  land. 

"(Signed)  R.  FITZROY." 

Admiral  FitzRoy  writes  : — 

"  This  marine  barometer,  for  Her  Majesty's  service,  is  adapted  to  general  purposes. 

"  It  differs  from  barometers  hitherto  made  in  points  of  details,  rather  than  principle  : — 
1.  The  glass  tube  is  packed  with  vulcanised  India-rubber,  which  checks  vibration  from  con- 
cussion, but  does  not  hold  it  rigidly,  or  prevent  expansion.  2.  It  does  not  oscillate  (or 
pump),  though  extremely  sensitive.  3.  The  scale  is  porcelain,  very  legible,  and  not  liable 
to  change.  4.  There  is  no  iron  anywhere  (to  rust*).  5.  Every  part  can  be  unscrewed, 
examined,  or  cleaned,  by  any  careful  person. 

"  These  barometers  are  graduated  to  hundredths,  and  they  will  be  found  accurate  to  that 
degree,  namely,  the  second  decimal  of  an  inch." 

19.  Negretti  &  Zambra's  Short  Tube  Barometer,  specially  constructed 
by  N".  &  Z.  for  Balloon  experiments,  Altitude  Measurements,  or  for  use  at 
elevated  mountain  stations.  price  £770 

45,    COENHILL,    E.G.,   AND    122,    REGENT   STREET,    W.,    LONDON. 


FIG.  15. 

FIG.  16. 

FIG.  12. 

20.  Negretti  and  Zambra's  Students'  Standard  Barometer.  In 
laying  off  and  dividing  the  scale  of  this  instrument,  allowances  have  been 
made  to  compensate  for  the  ordinary  rise  and  fall  of  the  mercury,  making  it 
sufficiently  accurate  for  observers  who  do  not  wish  to  incur  the  expense  of 
Fortin's  arrangement  for  adjusting  to  a  Zero  Point.  Fig.  16.  Price  £550 



21.  Magnifying  the  Barometer  Eange. — The  limit 
within  which  the  barometric  column  oscillates,  does  not 
exceed  four  inches  for  extreme  raDge,  while  the  ordinary 
range  is  confined  to  about  two  inches  ;  and  it  has  often  been 
felt  that  the  utility  of  the  instrument  would  be  much  enhanced 
if  by  any  means  the  scale  indications  could  be  increased  in 
length.  This  object  has  been  sought  to  be  obtained  by  bend- 
ing  the  upper  part  of  the  tube  from  the  vertical,  so  that  the 
inches  on  the  scale  could  be  increased  in  length.  Such  an 
instrument  was  invented  by  Sir  S.  Moreland,  in  1772,  and 
named  by  him  "  the  Diagonal  Barometer."  Another  variation 
of  Barometer,  invented  by  M.  Cassini,  and  improved  by  M. 
J.  Benoulli,  about  the  same  date,  was  constructed  with  the 
upper  part  of  the  tube  expanded  into  a  large  Bulb,  and  the 
lower  part  of  the  tube  giving  the  scale  is  very  much  contracted 
in  the  bore,  and  bent  at  a  right  angle.  From  this  the  instru- 
ment was  termed  the  Horizontal  Rectangular  Barometer. 
The  upper  part  of  the  Barometer  tube  has  also  been  forme  d 
into  a  Spiral,  with  the  scale  placed  along  it,  which  is  thus 
greatly  enlarged. 

Another  form  of  Extended  Range  Barometer  was  in- 
vented and  made  by  M.  Amontons  in  1695,  and  named  by 
him  the  Pendent  Barometer.  It  is  a  Mercurial  Barometer, 
the  upper  half  of  the  tube  (the  indicating  portion)  being  of 
smaller  internal  diameter  than  the  lower  half.  By  this 
arrangement,  an  extended  range  of  scale  is  obtained.  The 
lower  end  of  this  tube  is  open,  and  the  mercury  supported  in  it  at 
varying  distances  by  the  upward  pressure  of  the  atmosphere, 
very  similar  in  action  to  that  of  Howson's  Barometer. 

Like  the  previously  described  instruments,  this  Barometer 
can  only  be  regarded  as  a  scientific  curiosity,  and  is  very 
subject  to  become  out  of  adjustment  in  transit.  This  is 
unfortunate,  as  these  Barometers  are  curiously  sensitive,  or 
perhaps  we  should  more  properly  say,  the  movements  of  the 
mercury  are  rendered  more  visible. 

These  methods  of  enlargement  Barometer  indications  are 
not  so  convenient  as  Dr.  Hook's  elegant  arrangement  em- 
ployed in  the  ordinary  Dial  or  Wheel  Barometer.  Therefore 
they  are  now  very  little  used,  and  are  of  very  little  practical 

FIG.  18. 

45,    COENHILL,   E.G.,   AND    122,   EEGENT   STEEET,   W.,    LONDON. 


FIG.  18*. 

22.  Negretti  and  Zambra's  Howson's  Patent  Long 
Range  Barometer. 

"  The  object  of  this  instrument  is  to  add  to  the  sensitive- 
ness of  the  ordinary  mercurial  column,  by  giving  it  an  increased 
range,  a  desideratum  which  it  appears  to  accomplish  with 
simplicity  and  efficiency. 

"  The  principle  of  construction -will  be  understood  on  refer- 
ence to  the  diagram,  fig.  18,  which  represents  a  section  of  the 
working  parts  of  the  barometer  divested  of  its  case. 

"  A  is  the  barometer  tube,  which  is  of  large  dimensions, 
and  of  greater  length  than  usual  in  proportion  to  the  additional 
length  of  range  which  it  is  intended  to  apply  to  it.  The  cistern, 
B,  is  of  a  tubular  shape,  so  as  to  contain  a  fixed  depth  of 
mercury,  also  determinable  by  the  range.  To  the  bottom  of 
this  cistern  is  attached,  concentrically,  a  light  glass  stem  or 
long  hollow  tube,  S,  hermetically  sealed,  springing  to  a  height 
of  about  28  inches  above  the  fixed  level  of  the  mercury  in  the 

"  When  all  the  parts  are  in  situ,  as  in  the  diagram,  fig  18*, 
the  tube  A  being  freely  suspended,  and  the  whole  filled  with  the 
requisite  quantity  of  mercury,  the  immediate  result  of  the  arrange- 
ment is  that  the  cistern  hangs  in  suspension  without  any  fixed 
support.  The  stem  C,  it  will  be  observed,  passes  up  the  tube 
A,  and  terminates  a  little  below  the  upper  level  of  the  mercury 
M :  its  upper  end  is  therefore  exposed  to  no  more  downward 
pressure  than  that  caused  by  the  weight  of  the  mercury  above 
it,  and  consequently  there  is  an  excess  of  upward  pressure  from 
the  atmosphere  exteriorly  which  tends  to  raise  the  cistern. 

"  If  we  suppose,  for  instance,  the  area  of  the  stem  to  be  half 
a  square  inch,  and  its  top  to  be  covered  with  1  inch  in  depth  of 
mercury  (the  space  above  being  of  course  a  vacuum),  there  will 
be  a  pressure  tending  to  push  the  cistern  downwards  of  only 
J  Ib.  or  thereabouts,  while  the  atmosphere  will  be  pressing 
upwards  on  an  equal  area  with  a  force  of  7  Ibs.  or  more.  Thus 
it  will  be  seen  that  when  the  excess  of  upward  pressure  is 
exactly  balanced  by  the  weight  of  the  cistern  with  its  stem, 
and  contained  mercury  up  to  the  level  &,  an  equilibrium  will 
be  established  which  will  keep  the  cistern  stationary.  If  from 
any  cause  the  cistern  should  become  lighter,  it  will  ascend  :  if 
it  should  become  heavier,  it  will  descend,  and  the  extent  to 
which  it  will  move  in  either  case  will  be  limited  by  the  immer- 


sion  or  emersion  of  the  tube  A,  or  rather  of  the  glass  which  bounds  it.  This 
is  precisely  the  action  which  takes  place  under  the  influence  of  the  fluctuations 
of  atmospheric  pressure.  For,  let  the  internal  area  of  the  tube  A  be  supposed 
to  be  1  square  inch,  and  let  a  barometric  rise  take  place  equal  to  1  inch  by  the 
ordinary  standard,  it  is  evident  that  a  cubic  inch  of  mercury  will  under  these 
conditions  leave  the  cistern,  pass  into  the  tube,  and  accumulate  above  the  top 
of  the  stem  :  consequently  the  cistern,  being  relieved  of  a  portion  of  its  weight, 
will  be  pushed  upwards  until  the  cubic  inch  is  replaced  by  the  immersion  of 
the  glass  of  the  tube  A.  As  soon  as  this  point  has  been  reached  it  will  become 
stationary  ;  but  in  the  meantime,  in  the  act  of  rising,  it  will  have  pushed  up 
the  entire  column  before  it ;  so  that  the  total  rise  of  the  top  of  the  column  will 
be  compounded  of  two  motions,  viz.,  of  the  ordinary  barometric  rise,  and  the 
rise  of  the  cistern.  The  converse  of  this  takes  place  on  the  occurrence  of  a 
diminution  of  atmospheric  pressure.  When  the  column  moves,  the  cistern 
follows  it,  and  when  the  cistern  moves,  it  drags  the  entire  column  with  it. 

"  The  instrument  has  been  in  use  for  many  years,  and  its  movements  have 
been  found  to  follow  with  accuracy  those  of  the  best  standard  Barometers.  Its 
sensitiveness  and  activity  during  storms  is  conspicuous.  There  is  also  another 
advantage  which  this  construction  confers,  viz.,  that  the  cistern  is  self-adjusting 
with  regard  to  its  level.  Readings  may  be  taken  to  three  places  of  decimals 
without  a  vernier,  and  without  any  adjustment  for  variation  of  level  in  the 
cistern.  At  the  same  time,  the  error  due  to  temperature  is  of  an  almost  in- 
appreciable amount."  *  Price,  in  Ornamental  carved  Oak  Case  as  fig.  18*.  £14  14  0 

23.  McNield's  Long  Range  Barometer. — A  barometer  designed  on  a 
directly  opposite  principle  to  the  one  just  described.  The  tube  is  made  to  float  on 
the  mercury  in  the  cistern.  It  is  filled  with  mercury,  inverted  in  the  usual 
manner,  then  allowed  to  float,  being  held  vertically  by  glass  points  or  guides.  By 
this  contrivance,  the  ordinary  range  of  the  barometer  is  greatly  increased.  As 
the  mercury  falls  in  the  tube  with  a  decrease  of  pressure,  the  surface  of  the  mer- 
cury in  the  cistern  rises,  and  the  floating  tube  rises  also,  which  causes  an 
additional  descent  in  the  column,  as  shown  by  graduations  on  the  tube.  With 
an  increase  of  pressure,  mercury  will  leave  the  cistern  and  rise  in  the  tube,  while 
the  tube  itself  will  fall,  and  so  cause  an  additional  ascent  of  mercury. 

Price,       £12     12     0 

Both  Howson's  and  McNield's  Barometers  are  constructed  by  Negretti  and 
Zambra  with  scales  of  from  five  to  eight  times  that  of  the  ordinary  standard. 
Their  sensitiveness  is  consequently  increased  in  an  equal  proportion,  and  they 
have  the  additional  advantage  of  not  being  affected  by  differences  of  level  in 
the  cistern. 

*  Extract  from  the  Proceedings  of  the  .British  Meteorological  Society,  Nov.  20th,  1861.    Vol.  i.  p.  81. 


Negretti   and   Zambra's    Self -compensating    Standard   Barometer 

consists  of  the  usual  form  of  standard  instrument,  but  attached  to  the  vernier 
is  a  double  rack  moved  by  one  pinion,  so  that  when  adjusting  the  vernier  in 
one  position,  the  second  rack  moves  in  the  opposite  direction,  carrying  along 
with  it  a  plunger  (the  exact  size  of  the  internal  diameter  of  the  tube)  dipping 
in  the  cistern,  so  that  whatever  displacement  has  taken  place  in  the  cistern, 
owing  to  the  rise  or  fall  of  the  mercury,  it  is  exactly  compensated  by  the 
plunger  being  more  or  less  immersed  in  the  mercury,  consequently  no  capacity 
correction  is  required.  Price,  £18  18  0 

Standard  Barometer,  with  Electrical  Adjustment. — This  barometer 
consists  of  an  upright  glass  tube  dipping  into  a  glass  cistern  of  mercury,  so 
contrived,  that  an  up-and-down  movement,  by  means  of  a  screw,  can  be  imparted 
to  it.  Through  the  top  of  the  tube  a  piece  of  platinum  wire  is  passed  and  her. 
metically  sealed.  The  cistern  also  has  a  metallic  connection,  so  that  by  means 
of  copper  wires  (in  the  back  of  the  frame)  a  galvanic  circuit  is  established ; 
another  connection  also  exists  by  means  of  a  metallic  point  dipping  into  the 
cistern.  The  circuit,  however,  can  be  cut  off  from  this  by  means  of  a  switch 
placed  about  midway  up  the  frame.  On  one  side  of  the  tube  is  placed  a  scale 
of  inches  ;  with  a  small  circular  vernier,  divided  into  100  parts,  connected  with 
the  dipping  point,  and  working  at  right  angles  with  this  scale. 

Eor  taking  an  observation,  a  galvanic  battery  is  connected  by  two  binding 
screws  at  the  bottom  of  the  frame.  The  switch  is  turned  upwards,  thereby 
disconnecting  the  dipping  point ;  the  cistern  is  then  screwed  up,  so  that  the 
mercury  in  the  tube  is  brought  into  contact  with  the  platinum  wire  at  the  top  ; 
the  instant  this  is  effected  a  magnetic  needle  arranged  as  a  galvanometer  on  the 
barometer  board  will  be  deflected.  The  switch  is  now  turned  down ;  by  so 
doing  the  connection  with  the  upper  platinum  wire  is  cut  off,  and  established 
between  the  dipping  point  carrying  the  circular  vernier  and  the  bottom  of  the 
cistern ;  the  point  is  now  screwed  by  means  of  the  milled  head  until  the  needle 
is  again  deflected,  and  the  line  on  the  vernier  cutting  the  division  on  the  scale 
is  the  exact  reading  of  the  barometer.  Price,  £18  18  0 

The  two  Barometers  above-mentioned  were  exhibited  1y  Negretti  and  Zambra  at  the 
Meeting  of  the  Royal  Meteorological  Society,  March,  1886. 

45,    CORNHILL,    E.G.,    AND    122,    BEQENT    STREET,    W.,   LONDON.  17 

24.  The  Water  Barometer  first  constructed  by  Professor  Daniell  of  King's 
College  for  the  Royal  Society  in  1830  was  fitted  up  under  his  superintendence 
at  their  rooms  in  Somerset  House.  It  consisted  of  a  glass  tube  40  feet  in 
length  and  about  one  inch  in  diameter.  This  barometer  was  in  action  at 
Somerset  House  for  some  two  years,  and  a  series  of  observations  made  with  it 
showed  "  that  the  Water  Barometer  preceded  by  one  hour  the  indications  of  a 
mercurial  instrument  having  a  column  of  mercury  of  f  inch  diameter." 

On  the  removal  of  the  Royal  Society  from  Somerset  House  this  Water 
Barometer  was  taken  down  by  Messrs.  Negretti  and  Zambra,  refilled,  and 
mounted  by  them  at  the  Crystal  Palace,  Sydenham,  where  for  a  short  time  it 
excited  considerable  interest,  but  owing  to  various  causes  the  indications  were 
found  to  be  incorrect  scientifically.  Eventually  the  instrument  was  destroyed 
by  fire  during  the  winter  of  1866.  At  the  suggestion  of  Dr.  D.  Price  another 
Water  Barometer  was  erected  by  Mr.  Jordan  for  the  Crystal  Palace  Company  ; 
but  although  the  Water  Barometer  is  of  great  interest  as  a  weather  glass,  its 
indications  were  again  found  to  be  of  but  little  scientific  value,  owing  to  the 
effect  of  varying  temperature  on  the  aqueous  vapour  above  the  column  of 
water.  This  difficulty  led  to  the  substitution  by  Mr.  Jordan  of  glycerine  for 
water,  and  the  construction  of  the  now  well-known  Jordan  Glycerine  Barometer, 
one  of  which  is  erected  at  the  Times  office  and  one  also  at  the  Kew  Observatory 
by  a  grant  from  the  Royal  Society.  Mr*.  Whipple,  the  director  at  Kew,  states 
the  records  obtained  by  it  are  fairly  satisfactory. 

The  tube  of  the  Glycerine  Barometer  is  composed  chiefly  of  ordinary  com- 
position gas  tubing  of  f  inch  internal  diameter :  to  this  is  very  carefully  joined 
and  cemented  about  four  feet  of  glass  tube  one  inch  internal  diameter.  The 
upper  end  of  this  tube  is  formed  into  a  funnel-shaped  cup,  having  a  conical 
shaped  stopper  of  India-rubber  arranged  for  conveniently  filling  and  adjusting 
the  instrument.  The  glass  portion  of  the  tube  is  the  indicating  part  of  the 
barometer.  Suitable  divided  scales  are  placed  at  the  sides  of  the  glass  portion 
of  the  tube,  one  showing  inches  and  tenths  of  absolute  measure,  and  on  the 
opposite  side  another  scale  of  equivalent  values  of  a  column  of  mercury  at  a 
temperature  of  60°  Fahrenheit. 

R.  H.  Scott,  Esq.,  of  the  Royal  Meteorological  Society,  writes  that  during 
the  continuance  of  a  violent  gale  and  storm,  "  a  fall  of  more  than  16  inches 
of  glycerine  has  been  noted."  "The  movements  of  the  glycerine  column  are 
10' 76  times  greater  than  those  of  the  mercurial  column  at  the  standard  tem- 
perature, 333*57  inches  of  glycerine  being  equivalent  to  31  inches  of  the 
mercurial  barometer."  We  are  chiefly  indebted  for  these  details  of  the  Glycerine 
Barometer  to  Mr.  Jordan's  Pamphlet,*  to  which  we  refer  our  readers  for  further- 
particulars  as  to  the  construction  and  use  of  the  instrument. 

*  The  Glycerine  Barometer  with  Plate  and   Table  of  Corrections  for  Temperature,  by  James  B.  Jordan^ 
Mining  Record  Office  Museum  of  Practical  Geology.    Price,  One  Shilling. 




It  will  be  seen  that  owing  to  the  great  length  of  the  tube,  viz.,  27  feet, 
Jordan's  Barometer  can  only  be  fitted  up  in  very  few  buildings.  To  gain  the 
advantage  of  so  extended  a  range  of  scale  in  a  convenient  sized  instrument, 
Messrs.  Negretti  and  Zambra  have  constructed  their 





24*.  The  Long  Range  or  Open  Scale  Barometer 
is  shown  in  section  in  fig.  19.  It  consists  of  a 
glass  tube  of  the  syphon  form ;  one  side  of  the 
syphon,  A,  or  closed  end,  being  about  33| 
inches  long,  and  the  other  only  a  few  inches  in 
length.  To  this  short  end  is  joined  a  length  of 
glass  tubing,  B,  of  a  much  smaller  (internal) 
diameter ;  both  tubes  are  of  equal  length,  the 
smaller  one  being  open  at  the  top.  The  large  ||_£2|| 
tube,  A,  is  filled  with  Mercury,  and  the  small 
tube,  B,  partly  filled  with  Glycerine,  a  fluid 
many  times  lighter  in  specific  gravity  than 
Mercury ;  the  rising  and  falling  of  the  mer- 
curial column  in  the  large  tube  having  a  lighter 
fluid  to  balance,  and  that  dispersed  over  a 
larger  space  by  reason  of  the  difference  in  the 
diameter  of  the  two  tubes,  a  longer  range  is 
obtained,  due  loth  to  the  unequal  capacity  of  the 
tivo  tubes  and  the  difference  in  the  specific  gravity 
of  Mercury  and  Glycerine. 

The  range  of  these  barometers  is  from  six  to 
ten  inches  to  the  inch  of  the  ordinary  Mercurial 
Barometer,  yi^  of  an  inch  can  easily  be 
observed  without  the  use  of  a  vernier.  It  is  a 
most  interesting  instrument,  as  from  the  extremely  extended 
scale  the  slightest  variation  is  plainly  visible.  The  actual 
size  and  form  is  about  that  of  an  ordinary  Barometer,  as 
seen  in  fig.  20  ;  extreme  length  about  40  inches. 


FIG.  20. 

FIG.  19. 

Price,  as  fig.  20      ... 
Do.,  with  Portable  Stop  Cock 

£5     5 
5  10 

45,    CORNHILL,    B.C.,    AND    122,    KEGENT    STREET,    W.,    LONDON. 



For  many  years  a  good  and  accurate  self-recording  barometer  was  much 
desired.  This  want  is  now  satisfactorily  supplied,  not  by  one,  but  by  several 
descriptions  of  apparatus.  The  first  was  the  design  of  Admiral  Sir  A.  Milne, 
who  himself  constructed,  in  1857,  we  believe,  the  original  instrument,  which 
he  used  with  much  success. 

25.  Negretti  and  Zamtora's  improved  Self- 
Registering  Mercurial  Barometer  or  Baro- 
graph.— In  this  instrument  the  various  parts  of 
the  mechanism  have  been  so  modified  and  arranged 
that  the  record  on  the  papers  is  obtained  with  the 
greatest  precision  and  delicacy.  The  engraving 
(fig.  21)  will  give  the  general  details.  It  should, 
however,  be  mentioned,  that  it  is  not  a  picture  of 
the  outward  appearance  of  the  instrument.  The 
position  of  the  barometer  should  be  behind  the 
clock  ;  it  is  represented  on  one  side  merely  for  the 
purpose  of  clearly  illustrating  the  arrangement. 
The  instrument  has  a  large  syphon  barometer  tube, 
in  which  the  mercurial  column  is  represented. 
On  the  mercury  at  A,  floats  a  glass  weight, 
attached  to  a  silk  cord,  the  other  end  of  which  is 
connected  to  the  top  of  the  arched  head  on  the 
short  arm  of  a  lever-beam.  The  long  arm  of  this 
beam  is  twice  the  length  of  the  short  arm,  for  the 
following  reason.  As  the  mercury  falls  in  the  long 
limb,  it  rises  through  an  equal  space  in  the  short 
limb  of  .the  tube,  and  vice  versa.  But  the  barometric 
column  is  the  difference  of  height  of  the  mercury 
in  the  two  limbs  ;  hence  the  rise  or  fall  of  the  float 
through  half-an-inch  will  correspond  to  a  decrease 
FIG.  21.  or  an  increase  of  the  barometric  column  of  one 

inch.  In  order,  then,  to  record  truly  the  movements  of  the  mercurial  column, 
and  not  those  of  the  float,  the  arm  of  the  beam  connected  with  the  float  is  only 
half  the  radius  of  the  other  arm.  From  the  top  of  the  large  arched  head  a  piece 
of  watch-chain  descends,  and  is  attached  to  the  marker,  B,  which  properly 
counterpoises  the  float,  A,  and  is  capable  of  easy  movement  along  a  groove  in 
a  brass  bar,  so  as  to  indicate  the  barometric  height  on  an  ivory  scale,  C, 
fixed  on  the  same  vertical  framing.  On  the  opposite  side  of  the  marker,  J?, 
is  a  metallic  point,  which  faces  the  registration  sheet  and  is  nearly  in 



contact  with  it.  The  framing,  which  carries  the  scale  and  marker,  is  an 
arrangement  of  brass  bars,  delicately  adjusted  and  controlled  by  springs,  so 
as  to  permit  of  a  quick  horizontal  motion  being  communicated  to  it  by  the 
action  of  the  hammer,  E,  of  the  clock,  whereby  the  point  of  the  marker  is 
caused  to  impress  a  dot  upon  the  paper.  The  same  clock  gives  rotation  to  the 
cylinder,  D,  upon  which  is  mounted  the  registering  paper.  The  clock  must  be 
re- wound  when  a  fresh  paper  is  attached  to  the  cylinder,  which  may  be  daily, 
weekly,  or  monthly,  according  to  construction  ;  and  the  series  of  dots  impressed 
upon  the  paper  shows  the  height  of  the  barometric  column  every  hour  by  day 
and  night.  The  space  traversed  by  the  marker  is  precisely  equal  to  the  range 
of  the  barometric  column. 

Price,  in  an  Ornamental  Oak  Case,  fig.  21     £18  18     0  and  22     0     0 

26.  King's  Self  -  Registering 
Barometer.  Mr.  Alfred  King,  Engineer 
of  the  Liverpool  Gas-Light  Company, 
designed,  in  1854,  a  barometer  to  register, 
by  a  continuous  pencil- tracing,  the  varia- 
tions in  the  weight  of  the  atmosphere ; 
and  a  highly-satisfactory  instrument,  on 
his  principle,  and  constructed  under  his 
immediate  superintendence,  was  erected 
at  the  Liverpool  Observatory. 

Fig.  22  is  a  front  elevation  of  this 
Barometer.  A,  the  barometer  tube,  is 
three  inches  internal  diameter,  and  it 
floats  freely  (not  being  fixed  as  usual)  in 
the  fixed  cistern,  B,  guided  by  friction- 
wheels,  W.  The  top  end  of  the  tube  is 
fastened  to  a  chain,  which  passes  over  a 
grooved  wheel,  turning  on  friction  rollers. 
The  other  end  of  the  chain  supports  the 
frame,  D,  which  carries  the  tracing 
pencil.  The  frame  is  suitably  weighted 
and  guided,  and  faces  the  cylinder,  C, 
around  which  the  tracing  paper  is 
wrapped,  and  which  rotates,  once  in 
twenty-four  hours  by  a  clock  movement. 
For  one  inch  change  in  the  mercurial 
column  the  pencil  is  moved  through  five 
inches,  so  that  the  horizontal  lines  on  the 

FIG.  22. 

45,  CORNHILL,  E.G.,  AND  122,  REGENT  STREET,  W.,  LONDON.        2T 

tracing,  which  are  half  an  inch  apart,  represent  one-tenth  of  an  inch  change  in 
the  barometer.  The  vertical  lines  are  hour  lines,  and  being  nearly  three- 
quarters  of  an  inch  apart,  it  will  be  seen  that  the  smallest  appreciable  change 
in  the  barometer,  and  the  time  of  its  occurrence,  are  recorded.  The  barometer 
in  this  instrument  is  similar  to  Mr.  McNeild's  "  Long-Range  Barometer," 
described  page  16.  Constructed  to  order  £280  to  £300 


27.  The  Aneroid  Barometer.  The  extremely  ingenious  instrument 
called  the  Aneroid,  is  no  less  remarkable  for  the  scientific  principles  of  its  con- 
struction and  action,  than  for  the  nicety  of  its  mechanism.  As  its  name  implies, 
it  is  constructed  "  without  fluid."  It  was  invented  by  M.  Vidi,  of  Paris.  In 
the  general  form  in  which  it  is  made  it  consists  of  a  brass  cylindrical  case 
about  five  inches  in  diameter  and  two  inches  deep,  faced  with  a  dial 
graduated  and  marked  similarly  to  the  dial-plate  of  a  "  wheel-barometer,"  upon 
which  the  index  or  pointer  shows  the  atmospheric  pressure  in  inches  and 
decimals  in  accordance  with  the  mercurial  barometer.  Within  the  case,  is 
placed  a  flat  metal  box  made  of  German  Silver,  generally  not  more  than  half  an 
inch  deep  and  about  two  inches  or  a  little  more  in  diameter,  from  which  nearly 
all  the  air  is  exhausted.  The  top  and  bottom  of  this  box  is  corrugated  in  con- 
centric circles,  so  as  to  yield  inwardly  to  external  pressure,  and  return  when  it 
is  removed.  The  pressure  of  the  atmosphere  continually  changes,  and  with  this 
varying  pressure,  the  top  and  bottom  of  the  box  approach  to  and  recede  from 
each  other  by  a  small  quantity  ;  but  the  bottom  being  fixed  to  the  base,  nearly 
all  this  motion  takes  place  on  the  top.  The  top  of  the  box  is  elastic,  and  rises 
and  falls  according  as  the  compressing  force  lessens  or  increases.  To  the  eye 
these  expansions  and  contractions  are  not  perceptible,  so  small  is  the  motion. 
But  they  are  rendered  very  evident  by  a  delicate  mechanical  arrangement, 
communicating  with  a  system  of  levers  ;  and,  by  the  intervention  of  a  piece  of 
watch-chain  and  a  fine  spring  passing  round  the  arbour,  turning  the  index  to 
the  right  or  left,  according  as  the  external  pressure  increases  or  decreases. 
Thus,  when  by  increase  of  pressure  the  vacuum  box  is  compressed,  the 
mechanism  transfers  the  movement  to  the  index,  and  it  moves  to  the  right ; 
when  the  vacuum  box  expands  under  diminished  pressure,  the  motion  is 
reversed,  and  the  index  moves  to  the  left.  As  the  index  traverses  the  dial, 
it  shows  upon  the  scale  the  pressure  corresponding  with  a  good  mercurial 

The  Aneroid  being  placed  under  the  receiver  of  an  air  pump  the  scale  is  laid 
off  to  correspond  with  a  Mercurial  Barometer  Gauge,  and  afterwards  compared 
and  corrected  by  a  Standard  instrument. 


The  engraving  ("fig.  23)  represents  the  latest  improved  mechanism  of  an 
aneroid.  The  outer  casing  and  face  of  the  instrument  are  removed,  but  the 
index  hand  is  left  attached  to  the  arbour.  A  is  the  corrugated  vacuum  box 

which  has  been  exhausted  of  air  through 
the  tube  J,  and  hermetically  sealed  by 
soldering.  B  is  a  powerful  curved 
spring,  resting  in  gudgeons  fixed  on  the 
base-plate,  and  attached  to  a  socket  be- 
hind, Fj  in  the  top  of  the  vacuum  box. 
A  lever,  (7,  joined  to  the  stoub  edge  of 
the  spring,  is  connected,  by  the  bent 
lever  at  I),  with  the  chain,  .E7,  the  other 
end  of  which  is  coiled  round,  and  fastened 
FIG  23.  to  the  arbour,  F.  As  the  box,  A,  is  com- 

pressed by  the  weight  of  the  atmosphere  increasing,  the  spring,  J9,  is  tightened, 
the  lever,  (7,  depressed,  and  the  chain,  E,  uncoiled  from  F,  which  is  thereby 
turned  so  that  the  hand,  H,  moves  to  the  right.  In  the  meanwhile  the  spiraj 
spring,  G,  coiled  round  F,  and  fixed  at  one  extremity  to  the  frame- work,  and  by 
the  other  to  F,  is  compressed.  When,  therefore,  the  pressure  decreases,  A 
and  B  relax,  by  virtue  of  their  elasticity  ;  E  slackens,  G  unwinds,  turning  F, 
which  carries  the  index  hand,  H,  to  the  left.  Near  /  is  shown  an  iron  pillar, 
cast  as  part  of  the  stock  of  the  spring,  B.  A  screw  works  in  this  pillar  through 
the  bottom  of  the  plate,  by  means  of  which  the  spring,  J?,  may  be  so  adjusted 
to  the  box,  A,  as  to  set  the  index,  H,  to  read  on  the  scale  in  accordance  with 
the  indications  of  a  Mercurial  Barometer.  In  the  higher  class  of  aneroid  baro- 
meters, the  lever,  C,  is  formed  of  a  compound  bar  of  brass  and  steel,  so  skilfully 
arranged  as  to  perfectly  compensate  for  the  effects  of  extreme  variations  of 

The  greatest  perfection  in  Aneroids  is  now  attained  by  having  as  perfect 
and  dry  a  Vacuum  as  possible.  Compensation  being  obtained  by  the  compound 
metal  bar  previously  mentioned. 

A  Thermometer  is  sometimes  attached  to  the  Aneroid,  as  it  is  convenient 
for  indicating  the  present  temperature  of  the  air,  but  for  accuracy  and  safety 
from  breakage,  N.  and  Z.  recommend  the  use  of  a  separate  Thermometer. 

Admiral  FitzRoy,  in  his  Barometer  Manual,  writes  :  "  The  Aneroid  is  quick 
in  showing  the  variation  of  atmospheric  pressure  ;  and  to  the  navigator  who 
knows  the  difficulty,  at  times,  of  using  barometers,  this  instrument  is  a  great 
boon,  for  it  can  be  placed  anywhere,  quite  out  of  harm's  way,  and  is  not  affected 
by  the  ship's  motion,  although  faithfully  giving  indication  of  increased  or 
diminished  pressure  of  air.  In  ascending  or  descending  elevations,  the  hand 
or  the  Aneroid  may  be  seen  to  move  (like  the  hand  of  a  watch),  showing  the 

45,    CORNHILL,    E.C.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


height  above  the  level  of  the  sea,  or  the  difference   of  level  between  places  of 

Aneroid  barometers,  if  occasionally  compared  with  a  mercurial  standard, 
are  similar  in  their  indications,  and  valuable  ;  but  it  must  be  remembered  that 
for  exact  scientific  observation,  the  Aneroid  barometer  cannot  be  put  into 
comparison  with  the  mercurial  column  for  strict  accuracy,  although  its  con- 
venient size  and  great  sensibility  render  it  most  useful  for  obtaining  observations 
where  a  mercurial  instrument  is  inconvenient  to  carry. 

Col.  Sir  H.  James,  R.E.,  in  his  Instructions  for  taking  Meteorological  Obser- 
vations, says  of  the  Aneroid  :  "  This  is  a  most  valuable  instrument,  it  is  ex- 
tremely portable.  I  have  had  one  in  use  for  upwards  of  ten  years." 

One  of  the  objects  of  Mr.  Glaisher's  experiments  in  balloons  was  "to 
compare  the  readings  of  an  Aneroid  barometer  with  those  of  a  mercurial  baro- 
meter." In  the  comparisons  the  readings  of  the  mercurial  barometer  were 
corrected  for  index-error  and  temperature.  Speaking  of  Aneroid  indications,* 
Mr.  Glaisher  remarks  : — 

"  A  third  (Aneroid)  graduated  down  to  five  inches,  and  most  carefully  made 

and  tested  under  the  air- 
pump  before  use,  read  the 
same  as  the  Mercurial 
Barometer  throughout  the 
high  ascent  to  seven  miles, 
September  5th,  1862.f  I 
have  taken  this  instrument 
up  with  me  in  every  sub- 
sequent high  ascent,  and 
it  has  always  read  the  same 
as  the  Mercurial  Baro- 
meter. These  experiments 
prove  that  an  Aneroid  can 
be  made  to  read  correctly 
at  low  pressures. 

"  I  may  mention  that  on 
several  occasions,  Aneroid 
Barometers  have  been 
taken  whose  graduations 
have  been  too  limited  for 
the  heights  reached  :  these 
-p  24  have  not  broken  or  become 

*  Travels  in  the  Air.    By  F.  Glaisher.     Page  89.  The  Aneroid  Barometer, 
f  Wolverhampton  to  Cold  Weston,  near  Ludlow,  September  5th,  18G2. 



FIG.  25.  FIG.  26. 

deranged  by  being  subjected  to  a  much  less  pressure  than  they  were  prepared 
for,  but  have  resumed  their  readings  on  the  pressure  again  coming  within 
their  graduations."  The  Aneroids  used  by  Mr.  Glaisher  were  made  for  him 
by  Messrs.  Negretti  and  Zambra. 

Directions  for  using  the  Aneroid. — Aneroids  are  generally  suspended  with 
the  dial  vertical ;  but  if  they  be  placed  with  the  dial  horizontal,  the  indications 
differ  a  few  hundredths  of  an  inch  in  the  two  positions.  Therefore,  if  their 
indications  are  to  be  recorded,  the  instrument  should  be  read  off  alivays  in  the  same 

As  before  observed,  the  Aneroid  will  not  answer  for  exact  scientific  pur- 
poses, as  its  error  of  indication  changes  slowly,  and  hence  the  necessity  of  its 
being  set  from  time  to  time  with  the  reading  of  a  Standard  Barometer.  To 
allow  of  this  being  done,  at  the  base  of  the  outer  case  is  a  screw  in  connection 
with  the  spring  attached  to  the  vacuum  box.  By  applying  a  small  screw-driver 
to  this  screw,  the  spring  of  the  vacuum  box  may  be  tightened  or  relaxed,  and 
the  index  hand  adjusted  to  the  right  or  left  on  the  dial,  as  in  correcting  a  watch. 

28.  Pocket  Aneroid  Barometers. — The  patent  for  the  Aneroid  having 
expired,  Admiral  FitzRoy  urged  upon  Messrs.  Negretti  and  Zambra  the 
desirability  of  reducing  the  size  of  the  instrument  as  then  made,  as  well  as  of 
improving  its  mechanical  arrangement,  and  compensation  for  temperature. 
They  accordingly  at  great  expense,  labour,  and  experiment,  succeeded  in 
reducing  its  dimensions  to  two  inches  in  diameter,  and  an  inch  and  a  quarter 
thick.  The  exact  size  and  appearance  of  these  Aneroids  is  shown  by  fig.  24. 
For  prices  of  Aneroid  Barometers  see  page  29. 

45,   CORNHILL,    E.G.,   AND    122,    REGENT    STREET,   W.,    LONDON.  25 

29.  Watch  Aneroid. — Negretti  and  Zambra  have  still  further  reduced 
the  size  of  the  Aneroid  to  that  of  an  ordinary  watch,  our  engravings,  figs.  25, 
26  showing  their  exact  size.     By  a  beautifully  simple  contrivance,  a  milled  rim 
is  constructed  to  move  round,  and  carry  with  it  the  index  or  pointer  over  the 
scale  engraved  on  the  dial,  for  the  purpose  of  marking  the  reading,  so  that  any 
increase  or  decrease  of  pressure  may  be  readily  seen.     These  very  small  instru- 
ments are  found  to  act  quite  as  correctly  as  the  largest,  and  are  much  more 
convenient.     Besides   serving  the  purpose  of  a  weather-glass  in  the  house  or 
away  from  home,  if  carried  in  the  pocket,  they  are  admirably  suited  to  the 
exigencies  of  tourists  and  travellers.     They  may  be  had  with  scale  sufficient 
to  measure  heights  of  20,000  feet ;  with  a  scale  of  elevation  in  feet,  as  well  as  of 
pressure  in  inches,  engraved  on  the  dial.     The  scale  of  elevation,  which  is  for 
the   temperature  of  50°,    was  computed  by  Professor   Airy,  late  Astronomer 
Royal,  who  kindly  presented  it  to  Messrs.  Negretti  and  Zambra,  for  publication.* 
Moderate- sized  Aneroids,  fitted  in  leather  sling  cases,  are  found  very  serviceable 
to  pilots,  fishermen,  and  for  use  in  coasting  and  small  vessels,  where  a  mercurial 
barometer  cannot  be  employed,  because  requiring  too  much  space." 

Negretti  and  Zambra' s  Watch-sized  Aneroid  Barometers,  figs.  25  and  26, 
have  now  for  many  years  been  fully  tried  and  tested,  as  ordinary  Weather 
Indicators,  for  obtaining  Altitude  Measurements,  and  also  for  Mining  purposes. 
From  the  very  extensive  patronage  afforded  to  them  by  Government  authorities 
(for  Military  and  Naval  service),  Engineers,  Surveyors,  and  Scientific  Observers, 
&c.,  N.  and  Z.  feel  justified  in  giving  their  unqualified  recommendation  to 
these  instruments,  for  Travellers'  use,  as  being  both  accurate  and  convenient. 

30.  Our  woodcuts,  figs.  24,  25,  26,  show  form  and  actual  size  of  the  most 
useful  Aneroid  Barometers.  Fig.  24  being  our  Pocket  size.  Fig.  25  our  Watch 
size,  with  the  simple  Barometer  Scale  of  inches  and20ths  of  an  inch.    This  same 
size  instrument  is  manufactured  with  Altitude  Scales  ranging  from  10  to  20 
thousand  feet.     Fig.  26  is  of  similar  size  to  the  preceding,  but  has  the  Altitude 
Scale  arranged  to  revolve,  so  that  the  zero  or  0  of  this  scale  being  set  to  the 
point  occupied  by  the  Index  at  the  commencement  of  the  ascent,  the  elevation 
attained  above  the  starting  point  may  be  at  once  seen  in  a  rough  way  on  the 
scale.     The  divisions  of  this  scale  not  being  absolutely  similar  all  round,  causes 
an  error  in  the  reading,  therefore,  where  exact  observations  are  desired,  the  zero 
of  the  scale  should  be  placed  opposite  to  the  31  point,  and  the  indications  read 
off  in  the  usual  manner  by  inches  and  fractions,  their  value  being  known  by 
reference  to  the  Altitude  Tables  sent  with  the  instrument,  so  that  this  form  of 
Aneroid  combines  both  methods  of  observing  in  one  instrument. 

*  See  List  of  Books  on  Meteorology  at  end  of  this  seotiou. 



FIG.  27. 

Our  fig.  27  shows  one  of  the  most  convenient  arrangements  yet  introduced, 
viz.,  a  Watch-sized  Aneroid,  with  a  reliable  Thermometer  and  Compass.  The 
hinged  leather  case  containing  the  three  instruments,  being  but  little  larger 
than  an  ordinary  portemonnaie.  Price,  see  page  29. 

31.  Measurement  of  Heights  by  the  Aneroid. — The  dial  of  the  Watch 
Aneroid  for  determining  altitudes  is  engraved  with  two  scales  in   concentric 
circles,  the  inner  circle  being  divided  into  inches  and  tenths  of  an  inch,  corre- 
sponding with  the  scale  of  the  Mercurial  column  of  a   Standard  Barometer. 
The  outer  circle  is  divided  into  spaces  representing  100  feet,  each  tenth  division 
being  numbered  as  1,000,  2,000,  &c.     The  zero  point  of  this  circle  corresponds 
with  31  inches  of  the  Barometer  scale,  for  this  reason,  that  the  Barometer  never 
rises  so  high   as  31  inches,  consequently,  our  scale  of  feet  is  always  outside  the 
weather  range.     The  zero  of  the  feet  scale  has  nothing  whatever  to  do  with  the 
sea-level,   that  is  a  variable  point  and  must  be  determined  at    the  time   of 
observation  either  by  actual  measurement  at  half  tide  level,  or  by  computation 
from  a  known  height. 

32.  Measurement  of  Altitudes  above  Sea  Level. — In  order  to  deter- 
mine the  height  of  any  station  above  the  sea-level  with  this  instrument,  we  must 
notice  at  what  point  it  stands  at  the  shore ;  we  then  ascend,  and  on  reaching 
the  desired  point,   observe  the  position  of  the  index  on  the   dial.     We  then 
deduct  the  number  of  feet  opposite  the  reading  on  starting  from  that  against 
the  reading  at  the  elevated   station,  this  gives  the  height  above  the  level  of  the 
sea.     Thus,  if  at  sea-level,  the  barometer  stands  at  30  inches,  and  at  the  elevation 
it  stands  at  26  inches  we  get  900  feet,  deducted  from  4,800  feet,  giving  us  a 
height  of  3,900  feet,  and  so  on  for  the  other  points  of  the  scale. 

When  great  accuracy  is  required,  simultaneous  observations  must  be  taken 
at  the  two  stations  to  obviate  any  error  that  might  arise  from  a  change  of 
weather  between  the  times  of  observation. 

Further  instructions  for  altitude  measurement  will  be  found  in  Negretti 
and  Zambra's  Treatise  on  Meteorological  Instruments. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  27 

33.  "  Great  storms  are  invariably  preceded  by  a  fall  in  the  barometer  of 
from  '05  to  '10  of  an  inch  per  hour.  Storms  from  the  eastward  sometimes  give 
loss  local  warning,  but  they  are  well  foretold  by  the  increase  of  statical  force. 
Storms  of  a  cyclonic  character  travel,  it  has  been  found,  on  an  average  about 
20  miles  an  hour  towards  some  point  between  NE.  and  SE.,  generally  towards 
the  former.  They,  therefore,  take  about  twenty-four  hours  to  traverse  the 
British  Isles,  from  the  time  of  their  commencement  in  the  west  of  Ireland. 
The  east  coasts  may  thus  be  warned  one  day  in  advance  by  the  telegraph  ;  and 
as  the  approach  of  a  storm  can  be  foreseen  at  the  place  threatened  hours  before 
its  advent,  noticev  of  gales  may  usually  be  given  from  one  to  two  days  in 
advance.  As  regards  the  exact  time  and  locality,  the  prognostication  of  storms 
must  necessarily  present  much  difficulty.  The  forecaster  must  be  guided  in 
these  respects  rather  by  experience,  to  be  gained  by  practice,  than  by  princi- 
ples ;  little  information  can  be  given  without  going  into  a  complete  examination 
of  particular  storms,  each  of  which  would  present  points  of  difference." 

Strachan'Si  Weather  Forecasts. 


FIG.  28. 

34.  This  instrument  registers  automatically  with  ink  upon  a  ruled  paper 
chart  attached  to  a  vertical  cylinder  revolved  for  seven  days  by  means  of  a  Clock 
movement  inside  it.  The  fluctuations  of  atmospheric  pressure  act  upon  seven 
Aneroid  vacuum  chambers,  connected  by  an  exceedingly  simple  mechanical  con- 
trivance to  a  long  lever  arm  carrying  the  Pen,  by  which  a  magnified  diagram  is 
produced  upon  the  paper  on  the  cylinder  of  the  rise  or  fall  or  present  height  of 
the  Barometric  column.  These  papers  are  ruled  to  represent  inches  and  tenths 
of  the  Mercurial  Barometer  Scale.  A  small  Thermometer  is  mounted  upon  the 

base  of  the  instrument. 

Price,  in  a  Glazed  Cabinet,  as  shown  in  fig.  28        .'.£7100 

Kuled  Papers,  per  Hundred,  for  above  ...  18    0 


FIG.  29. 

35.  These  Instruments  are  arranged  to  show  the  various  fluctuations 
that  have  taken  place  in  the  Barometer  during  the  absence  of  the  observer. 
They  consist  of  a  carefully  finished  Aneroid,  and  an  eight-day  Clock ;  between 
these  is  placed  in  a  vertical  position,  a  revolving  cylinder  having  a  metallic 
paper  attached  to  it  ruled  to  coincide  with  the  inches  and  tenths  of  the 
barometer  scale.  Close  to  this  paper,  is  a  pencil  mounted  on  a  metallic  rod 
and  is  moved  up 'and  down  as  the  variation  of  atmospheric  pressure  acts  upon 
the  vacuum  chamber  of  the  Aneroid  ;  at  every  hour  this  pencil  is  made  to  mark 
the  paper  by  simple  mechanism  in  connection  with  the  clock. 

By  this  means  a  black  dotted  curved  line  is  produced  on  the  paper,  show- 
ing at  a  glance  the  present  height  of  the  barometer — whether  it  is  falling  or 
rising — for  how  long  it  has  been  doing  so,  and  at  what  rate  the  change  has 
taken  place — if  falling  or  rising  at  the  rate  of  one-tenth  of  an  inch  per  hour,  or 
one-tenth  in  twenty-four  hours  ;  all  of  which  are  particulars  most  essential  to 
know  when  foretelling  the  weather,  and  which  can  only  be  obtained  from  an 
ordinary  barometer  by  very  frequent  and  regular  observations. 

Our  engraving  (fig.  29.)  shows  the  full  mounting  of  the  Registering 
Aneroid,  combining  a  reliable  Timepiece  with  an  exceeedingly  interesting 
Meteorological  Instrument,  of  a  suitable  and  convenient  size  for  a  library  or 
dining  room  mantel-shelf. 

Recording  Aneroid  Barometer  with  Thermometer,  ag  shown  fig.  29 

Price,  £22    0    0 

Large  size        ditto        ditto        with  more  Ornamental  Mounting    .  27  10    0 

Haled  charts  for  the  above,  per  Hundred   ...',.  110 



Compared  and  Corrected  Scale  Aneroid,  Compensated  for 
temperature,  as  supplied  to  the  Royal  Navy  and  Meteorological 
Department  .  .  .  .  .-.  .  .  .  .550 

Surveyors'  or  Engineers'  Aneroid  Barometer  for  Altitude 
Measurements,  Compensated  for  temperature,  with  Revolving 
Ring,  carrying  Index,  range  of  Scale,  10,000  feet,  4J  inches 
diameter  ...........770 

Pull  Range  Engineers'  Altitude  and  Surveying  or  Balloon 
Aneroid,  corrected  and  Compensated  for  temperature,  with 
20,000  feet,  Altitude  scale  (See  engraving  in  Surveying  Instru- 
ment Section) 880 

Mining  Surveyors'   Aneroid  Barometer,  with  a  Scale  reading 

to  7,000  feet  above  the  Sea  Level  to  2,000  feet  below       .  5  10     0 

Leather  Case  with  Sling  Strap,  for  any  of  the  above          .       .       0126 

Pocket-Sized  Aneroid,  with  Revolving  Ring  carrying  Index 

(size  shown  in  fig.  24)  .  .  .  .  .  •  .  .  .440 

Mountain  Aneroid  Barometer,  Pocket-Size,  for  measuring 

Altitudes  to  10,000  feet,  Compensated  for  temperature  550 

Ditto         ditto         ditto          to  20,000  feet,  fig.  24         .         .         .060 

Watch-Sized     Aneroid     Barometer,     of    best     Construction, 
Compensated        for        temperature,         for        Meteorological 
Observations  or  Altitude  Measurements  to  10,000  feet, 
(size  shown  in  fig.  26)       .          .          .          .          .          .          .          .550 

Watch-Sized  Aneroid  Barometer,  to  20,000  feet       .         .         .660 

Watch-Sized  Aneroid  Barometer,  with  Devolving  Altitude  Scale 

for  10,000  or  20,000  feet  (Seepage  25)     .         .  £5  10     0       6  10-    0 

Watch-Sized    Aneroid    Barometers,  with  Thermometer  and 

Compass,  in  Morocco  Pocket  Case  (fig.  27.)  .  £7  70  and  880 
Watch-Sized  Aneroid  Barometers  in  Solid  Gold  Cases  £15  15  0  to  21  0  0 
Ditto  ditto  in  Stout  Silver  Cases  .  .  £6  6  0  and  770 

Aneroid  Barometers  may  be  had  with  the  French  Metrical  Scale,  or  with  the 
English  and  corresponding  French  Scale  engraved  on  the  same  instrument. 

In  the  Section  of  our  Catalogue  "  Household  Barometers" — will  be  found 
an  illustrated  price  list  of  Aneroid  Barometers  in  Ornamental  Mountings, 
suited  for  the  Drawing  Room,  Library  or  Hall,  Ships  or  Yachts,  &c. 



FIG.  30. 

36.  Recording  Mercurial  Barometer  or  Barograph — for  automatically 
recording  the  variations  of  atmospheric  pressure  by  Photography.  Recom- 
mended by  the  Meteorological  Committee  of  the  Royal  Society,  and  used  by 
many  of  the  principal  Meteorological  Observatories. 

Fig.  30.  exhibits  the  general  arrangement  of  this  Barograph.  B  is  a 
Standard  Mercurial  Barometer  mounted  upon  a  mahogany  board  and  table, 
lacing  it  is  a  Drum  D,  to  which  is  attached  the  sensitised  Photographic  Paper. 
This  cylinder  is  revolved  once  in  24  or  48  hours  by  the  clock  C.  A  Condensing 
Lens,  E,  projects  the  light  from  the  Gas  Burner  G  through  the  space  F  over  the 
edge  of  the  mercurial  column,  and  thence  to  the  photographic  combination  lens  P, 
by  which  an  image  of  the  mercurial  column  is  formed  upon  the  sensitive  paper 
on  the  drum  for  a  regulated  space  of  time.  A  screen  or  shutter  L  acted 
upon  by  the  clock  cuts  off  this  image  for  the  space  of  four  minutes  every  two 
hours,  leaving  white  lines  upon  the  photographic  paper  representing  intervals 
of  two  hours.  At  the  side  of  the  barometer  tube  are  placed  two  zinc  rods 
attached  to  the  barometer  board  at  the  lower  ends  at  A.  These  rods  are  con- 
nected at  their  upper  ends  with  a  delicate  mechanical  arrangement  H  and  K, 
so  contrived  as  to  compensate  for  varying  Thermometric  changes  in  the 
mercurial  column,  these  variations  of  temperature  being  also  recorded  upon 
the  sensitive  paper. 

Attached  to  the  apparatus  is,  a  glass  cylinder,  M,  (of  the  same  internal 
diameter  as  the  Barometer  tube),  partly  filled  with  mercury,  into  which  is  placed 
a  sensitive  Standard  Thermometer  for  giving  the  temperature  of  the  surround- 
ing air.  B  is  an  adjusting  screw  for  regulating  the  height  of  the  barometer 
upon  its  support.  The  apparatus  when  in  action  is  enclosed  in  a  light  tight  box. 

The  Barograph  is  constructed  to  special  older,  the  cost  varying  from 
Sixty  to  Seventy  Guineas. 

45,    COEKHILL,    E.G.,    AND    122,    REGENT   STEEET,    W.,    LONDON. 




FIG.  31. 

37.  Undoubtedly  there  is  no  instrument  the  use  of  which  has  so  greatly 
increased  in  the  past  few  years  as  the  Thermometer :  not  only  is  it  now 
essential  to  the  scientific  observer,  the  meteorologist,  the  physician,  and  the 
chemist;  but  both  for  domestic  uses  and  manufacturing  processes  a  really 
accurate  thermometer  is  indispensable.  The  following  is  a  list  of  the  various 
forms  of  Standard  Thermometers  manufactured  by  Negretti  and  Zambra  ;  all  of 
these,  to  ensure  extreme  accuracy,  have  their  scales  divided  by  the  Prize 
Dividing  Engine  (fig.  31)  to  which  was  awarded  a  Prize  Medal  at  the  Great 
Exhibition  of  1851,  and  is  described  in  the  Report  of  the  Jurors  as  follows  : — 

"  This  is  a  beautifully  contrived  Divider  on  Ramsden's  principle,  with  a  long  fine  steel 
screw.  The  novelties  are — first,  the  wheel  at  the  screw  head,  which  is  divided  into  400  parts, 
and  has  cut  upon  its  circumference  (which  is  made  broad)  a  helix  screw,  in  the  thread  of 
which  runs  a  detent,  carried  along  by  the  run  of  the  thread  till  it  meets  a  stop  clamped  on 
the  helix  at  a  definite  point.  This  arrests  the  screw  at  this  point  of  the  motion. 
A  Prize  Medal  was  awarded." 

Messrs.  Negretti  and  Zambra  supply  Dividing  Engines  made  on  the  above 
principle  both  for  circular  and  straight  line  divisions. 

Price        .        .        £35  to  £150 

NOTE.— From  Report  of  the  Juries  of  the  Exhibition  of  1851.  "  Negretti  and  Zambra 
are  the  only  exhibitors  in  the  British  portion  who  have  sent  Thermometers  with  their  stem* 
graduated — the  only  safe  instruments  for  delicate  experiments." 




Two  important  improvements  in  the  Tubes  and  Scales  of  Thermometers 
and  Barometers,  first  introduced  by  Negretti  and  Zambra,  have  become  so 
extensively  used  that  N.  and  Z.  deem  a  short  notice  necessary  to  secure  to 
themselves  the  credit  of  the  inventions. 

The  first  improvement  is  the  introduction  of  a  white  Enamel  at  the  back  of 
Thermometer  Tabes,  which  renders  the  mercury  much  more  plainly  visible 
both  in  large    and  small-bore  tubes.     Most  of  the  extremely  delicate   Ther- 
mometers now  in  use  would  have  been  almost  useless  but  for  this  enamelling. 
This  invention  has  also  been  applied  to  the  back  of  Barometer  Tubes. 
The  second    invention  is  the  use  of   Porcelain  for  Scales  and  Dials  of 
Thermometers,  Barometers,  &c.,  in  place  of  metal,  ivory,  or  wood,  all  of  which 
so  soon  become  soiled  and  tarnished,  and  eventually  the  divisions  and  figures  are 
obliterated  by  the  action  of  the  atmosphere,  sea-water,  or  damp.     The  divisions 
and  figures  on  these  porcelain  plates  are  etched  in  with  fluoric  acid, 
and  the  colour  permanently  burnt  or  melted  in  by  fire. 
That  these  are  important  inventions  may  be  inferred  from 
their  use  in  all  thermometers  and  barometers  supplied  to 
the  Board  of  Trade  and  other  Government  departments. 

38.  Independent  Standard  Thermometer  (fig  32), 
with  Negretti  and  Zambra's  Enamelled  tube,  and  Engine, 
divided   into  either  Fahrenheit  or  Centigrade  scales,  the 
divisions  engraved   on  its    own    stem  and   mounted    on 
silvered    brass,    boxwood,    or    Negretti    and     Zambra's 
Patent  Porcelain  Scales. 

Price,     £550 
Kew  Certificate  for  above  Thermometer        050 

39.  Comparative  Standard  Thermometers  (fig.  33). 
These  Thermometers  are  made  by  comparison  with  great 
care,  from  an  accurate  standard,  correct  to  TV  °f  a  degree. 
Engine-divided  EnamelledTubes  mounted  on  Silvered  Brass 
or  Negretti  and  Zambra's  Patent  Porcelain  Scales,  with 
Mahogany  or  Oak  framing.       Price,    £220  and  £2  10    0 

FIG.  32. 

N.  &  Z's  Standard  Thermometers   are  made  from  selected  tubes,   the  internal 
diameter  of  which  is  ascertained  by  very  carefully  conducted  experiments.      They    rrT(-,    oo 
'J      are  also  strictly  tested  for  index   error,  and  a  copy  of  the   corrections,  if  any, 
furnished  with  each  instrument,  if  required. 

We  recommend  the  Standard  Thermometers  not  to  be  mounted  in  any  way, 
but  the  tube  to  be  enclosed  in  a  strong  outer  glass  jacket;  the  bulb  dipping 

45,    COKNHILL,    E.G.,    AND    122,    BEGENT   STREET,   W.,    LONDON. 


FIG.     34. 





FIG.  35. 

into  a  reservoir  of  mercury,  and  the  whole  hermetically  sealed,  as  in  our 
Standard  Deep-sea  Thermometers ;  by  these  means  the  bulb  is  effectually 
protected  from  the  pressure  of  the  atmosphere,  either  from  barometrical 
changes  or  difference  in  altitude,  and  the  divisions  on  the  stem  are  so  covered 
by  the  outer  glass  tube  that  they  cannot  be  effaced  or  become  invisible.  [ 

40.  Board  of  Trade  Thermometer. — It  consists  of  a  carefully  compared 
thermometer  with  ISTegretti  and  Zambra's  enamelled  tube  divided  on  its  stem  to 
degrees,  which  are  sufficiently  large  to  admit  of  sub-division  into  tenths  of  degrees 
and  ranging  from  0?  to  130°.  The  scale  is  of  Negretti  and  Zambra's  Patent 
Porcelain,  having  the  figures  etched  upon  it,  and  burnt  in  a  permanent  black. 
It  is  a  reliable  comparative  or  reference  thermometer,  adapted  for  almost  any 
ordinary  purpose,  and  cannot  be  injuriously  affected  by  any  chemical  action 
arising  from  air  or  sea- water.  (Fig.  34).  This  thermometer  is  employed  in 



the  Royal  Navy  and  for  the  observations  made  at  sea  for  the  Board  of  Trade 

and  Meteorological  Department. 

Price,  in  Neat  Japanned  Case 0  10     6 

Ditto        Copper  Case 0  12    6 

A  set  of  6  Ditto  ditto,  in  Copper  Cases,  fitted  in  a  Mahogany  Box  .      £2  10    0 

41.  Thermometers  of  Extreme  Sensitiveness. — Negretti  and  Zambra's 
Instantaneous  Thermometer,  with  Gridiron  form  of  bulb,  and  divided  upon  the 
stem,  as  shown  in  the  International  Exhibition  of  1862,  used  by  Mr.  Glaisher  in 
his  Balloon  ascents  to  obtain  very  rapid  thermometric  readings. 
(Fig.  35)  Price,     £3    3    0  to  £6    60 

42.  Thermometers,  very  delicate,   with  Spiral  or 
Coiled  bulbs,   engine-divided  upon  the  stem,  mounted  on 

boxwood,  metal,  or  opal  glass  scales.     Fig.  36. 

Price,     £220  and  £330 

43.  Earth  Thermometer — for  ascertaining  the  tem- 
perature of  the  soil  at  various  depths.     The  tube  is  about 
five   feet   long,    enclosed   in   stout   wood,    protected   and 
strengthened   by   metal   mountings    and   a   pointed    cap. 
The  scale  is  of  Negretti  and  Zambra's  Patent  Porcelain 
with    enamelled    and     burnt-in    divisions     and     figures. 
Figs.  37  and  38.  Price,     £1  15    0  and  £220 

44.  Earth  Thermometers  in  series  for  inserting   into 
the  ground  at  depths  of  6  inches,  12   inches,  24  inches,  48 
inches  and  120  inches.     These  thermometers  are  arranged 
with  a  scale  about  6  inches  above  the  earth. 

Price  for  the  series     £7    7     0 

45.  The  temperature  of  the  soil  is  a    very  important 
element   in  the    consideration    of    climate    especially    in 
connection  with  the  growth  of  vegetation. — "  It  has  been 
calculated  by  Mr.  Raikes,  from  experiments  made  at  Chat 
Moss,   that    the   temperature   of  the   soil   when    drained 
averages  10°  higher  than  it  does  when  undrained  ;  and  this 
is  not  surprising  when  we  find  that  lib.  of  water  evaporated 
from    1,000  Ibs.  of  soil  will    depress  the  whole  by  10°, 
owing  to  the  latent  heat  which  it  absorbs  in  its  conversion 
into  vapour." 

Faraday  has  calculated  that  the  average  amount  of  heat 
radiated  in  a  day  from  the  sun  on  each  acre  of  earth  in  the  latitude 
of  London,  is  equivalent  to  that  which  would  be  produced  from 
the  combustion  of  thirteen  thousand  four  hundred  and  forty 
pounds  of  coal. 
FIG.  38.  "  The  extremes  of  temperature  in  the  different  climates  of  the 

FIG.  37. 

45,    COENHILL,    E.G.,   AND    122,    EEGENT    STREET,   W.,    LONDON. 


earth  are  widely  separated  from  each  other,  and  the  range  of  the  thermometer 
is  always  greatest  in  the  interior  of  the  continents  within  the  tropics.  Mr 
Campbell,  in  the  country  of  the  Botchuanas,  saw  the  thermometer  at  8  a.m.  at 
28°,  and  at  84°  at  noon.  Mr.  Bruce  records  a  temperature  at  Gondar  of  113°. 
The  thermometer  at  Benares  rises  to  118°  ;  at  Sierra  Leone  the  thermometer  on 
the  ground  has  been  seen  to  rise  to  138P,  and  Humboldt  gives  many  instances  of 
the  temperature  of  the  torrid  zone  rising  to  118°,  120°,  and  129°.  At  one  time 
he  found  the  temperature  of  a  loose,  coarse-grained  granite,  in  the  sun,  140'5. 
In  the  Dukhun  at  a  height  of  3,090  feet  above  the  sea,  Col.  Sykes  once  saw  the 
thermometer  in  the  shade  at  105°,  the  range  of  the  thermometer  generally  being 
from  93°.9  to  40^.5." 

Slightly  beneath  the  surface  of  the  earth  in  the  tropics,  Humboldt  states 
temperatures  of  162°  and  134°  are  frequently  noted,  and  in  white  sand  at 
Orinoco  140°,  whilst  at  the  Cape  of  Good  Hope  under  the  soil  of  a  bulb  garden 
a  temperature  of  150°  is  recorded  by  Herschell.  In  China,  the  temperature  of 
water  of  the  fields  was  found  to  be  by  Meyer  113°  and  adjacent  sand  much 
hotter.  These  extremes  of  temperature,  which  would  cause  the  specific  gravity 
of  the  air  to  vary  from  1167  to  863,  may  serve  as  a  kind  of  measure  of  the  dis- 
turbing causes  which  interfere  with  the  velocity  and  local  direction  of  atmos- 
pheric currents  and  other  phenomena,  the  calculation  of  which  has  been  founded 
upon  mean  results. — DanielVs  Meteorology. 

It  is  stated  that  below  the  layer  of  constant  temperature  (estimated  at  about 
80  to  90  feet  from  the  earth's  surface),  the  temperature  is  found  to  increase  one 
degree  Centigrade  for  every  100  feet. 

46.  Earth  Thermometer,  Symons'  Arrange- 
ment, with  NEGUETTI  &  ZAMBBA'S  Slow  Action 
Thermometer.  An  iron  tube  closed  at  the  lower  end 
is  forced  down  into  the  earth,  and  secured  at  the 
desired  depth,  and  the  thermometer  lowered  down 
into  it  by  a  cord  or  chain  to  the  bottom,  and  allowed 
to  remain  a  sufficient  time ;  when  the  temperature  is 
to  be  noted,  it  is  quickly  drawn  up  and  its  indication 
observed.  The  great  advantage  of  this  method  of 
obtaining  Earth  Temperatures  is  that  the  ther- 
mometer can  at  any  time  be  compared  with  a  Standard, 
which  is  a  difficult  if  not  almost  impossible  operation 
to  be  carried  out  with  Thermometers  of  great  length 
(fig  39).  Also  see  fig.  49,  page  42. 

Price,  according  to  length,          £110  £150 

£1  10    0,        £2     2    0. 

By  means  of  these  instruments  it  has  been  found 
that  variations  depending  on  the  hour  of  the  day  are 


FIG.  39. 


scarcely  sensible  at  a  depth  of  2  or  3  feet,  and  that  those  which  depend  on  the 
time  of  year  decrease  gradually  as  the  depth  increases,  but  still  remain  sensible 
at  the  depth  of  25  feet,  the  range  of  temperature  during  a  year  at  this  depth 
being  usually  about  2  or  3  degrees  Fahr. 

The  mean  rate  of  increase  of  temperature  downwards  is  about  1  degree 
Fahr.  for  each  55  feet. 


Negretti  and  Zambra' s 
Patent  Self-registering  Maximum  Thermometer. 

The  only  Instrument  of  the  kind  adapted  for  transmission  to  India  and  the  Colonies. 
47.  Previous  to  the  Great  Exhibition  of  1851,  all  persons  interested  in  meteo- 
rological observations  were  constantly  annoyed  by  the  inconvenience  arising  from, 
the  imperfect  construction  of  Maximum  Thermometers ;  and  although  Messrs. 
Negretti  and  Zambra  at  that  time  exhibited  one  or  two  new  forms  of  instru- 
ments, nothing  new  in  principle  was  brought  forward.     A  thermometer,  old  in 
principle,  greatly  improved  by  Negretti  and  Zambra,  wherein  a  bubble  of  air 
caused  a  separation  in  the  mercurial  column  to  form  an  index,  was  exhibited  by 
them  ;  but  as  the  air  bubble  at  different  temperatures  assumed  different  lengths 
it  was  not  approved  by  the  Jury  appointed  to  examine  Meteorological  Instru- 
ments.    The  instruments  invented  by  Dr.  Rutherford  and   Six,  as  Maximum 
Thermometers,  had  both  proved  inefficient  for  the   purposes  required ;  and 
although   the  best  and  most  correct  forms  of  these  were  also  exhibited  by 
Negretti  and  Zambra,  they  still  saw  that  a  great  want  would  be  met  if  a  perfect 
instrument  could  be  invented  to  indicate  Maximum  temperatures,  all  the  above 
being  imperfect — Rutherford's  from  the  tendency  of  the  index  to  plunge  in  the 
mercury,  Six's  from  the  different  expansive  properties  of  the  alcohol,  mercury, 
&c.,  of  which  it  is  composed,  and  the  one  already  alluded  to,  not  only  from  the 
defects  before  noticed,  but  also  from  its  liability  to  resolve  itself  into  an  ordinary 
thermometer  when  used,  unless  in  the  hands  of  a  skilful  manipulator.     How  far 
the  New  Patent  Maximum  Thermometer  of  Negretti  and  Zambra  has  supplied 
all  these    deficiencies  may  be  judged  from  the  fact  that  in  all  the  principal 
Observatories  throughout  the  world  it  is  used,    to   the  exclusion  of  all  others, 
unless  for  the  purposes  of  comparison.     They  are  now  in  the  hands  of  all  our  most 
scientific  men,  and  have  given  universal  satisfaction.     The  simplicity  of  their 
construction  enables  the  most  uninitiated  in  thermometers  to  use  them  with 
confidence  and  safety  ;  and  another  important  feature  in  them  is  the  impossibility 
of  putting  them  out  of  order,  for  nothing  short  of  actual  breakage  can  in  any 
way  cause  them  to  fail. 

45,    COBNHILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,    LONDON.  37 

FIG  40. 

48.  Negretti  and  Zambra's  Patent  Self-registering  Standard 
Maximum  Thermometer,  consists  of  a  tube  of  mercury  mounted  on  an 
engraved  scale,  as  shown  in  fig  40.  The  thermometer  tube  above  the  mercury 
is  entirely  free  from  air ;  and  at  the  point  (A)  in  the  bend  above  the  ball,  is 
inserted  and  fixed  with  the  blow-pipe  a  small  piece  of  solid  glass,  or  enamel, 
which  acts  as  a  valve,  allowing  mercury  to  pass  on  one  side  of  it  when  heat  is 
applied ;  but  not  allowing  it  to  return  when  the  thermometer  cools.  When 
mercury  has  been  once  made  to  pass  the  valve,  which  nothing  but  heat  can  effect' 
and  has  risen  in  the  tube,  the  upper  end  of  the  column  registers  the  maximum 
temperature.  To  return  the  mercury  to  the  btflb,  we  must  apply  a  force 
equal  to  that  which  raised  it  in  the  tube ;  the  force  employed  is  gravity,  and  is 
applied  by  simply  lowering  the  bulb  end  of  the  thermometer,  when  the  gravity 
of  the  mercury  in  the  tube  will  be  sufficient  to  unite  it  with  that  in  the  bulb,  and 
thus  prepare  the  instrument  for  future  observation. 

Price,  mounted  with  Negretti  and  Zambra's  enamelled  tube  and  Patent 

Porcelain  or  Opal  glass  Scale,  fig.  40 £110 

The  following  is  an  extract  from  the  Report  of  the  Astronomer  Royal,  pub- 
lished shortly  after  the  invention  of  the  instrument — it,  however,  applies  more 
strongly  now,  inasmuch  as  the  intervening  years  have  fully  proved  the  efficiency 
and  value  of  this  invention : — - 

Report  of  the  Astronomer  Royal,  May,  1852. 

"  We  have  for  several  years  baen  very  much  troubled  by  the  failures  of  the  Maximum  Self-Eegistermg 
Thermometers,  especially  those  exposed  to  the  sun:  the  part  of  the  tube  in  which  the  index  ought  to 
slide  becomes  foul,  apparently  lined  with*  a  coat  of  metal,  and  the  index  is  immovable.  A  construction 
invented  by  Messrs.  Negretti  and  Zambra  appears  likely  to  evade  this  difficulty.  The  mercury  in  its 
expansion  is  forced  past  an  obstruction  in  the  tube  and  does  not  return  past  in  its  contraction.  No  index 
is  required  in  this  construction.  The  specimens  of  this  instrument  which  we  have  tried  answer  well." 

In  the  Quarterly  Report  of  the  Registrar  General,  about  the  same  time,  there 
is  the  following  annotation  : — 

l*  The  form  of  instrument  adopted  during  the  past  quarter  for  maximum  temperature  is  that  of 
Negretti  and  Zambra,  which  is  found  to  act  admirably." 

J.  GLAISHEE,  Esq.,  F.R.S.,  in  his  Lectures  on  the  Results  of  the  Great 
Exhibition,  delivered  at  the  Society  of  Arts,  at  the  suggestion  of  his  late 
Royal  Highness  the  Prince  Consort,  when  speaking  of  Meteorological 
Instruments  (page  363)  says  : — 

"  In.  maximum  and  minimum  thermometers  there  was  nothing  new  exhibited,  although  great  need  had 
long  existed  for  an  effective  Maximum  Thermometer.  Thanks  to  the  exhibition,  however,  this  want  has 

*  The  whole  of  Negretti  and  Zambra's  Standard  Thermometers  have  their  improved  enamelled  back 
tabes  and  are  Engine-divided  on  the  stem. 


since  been  supplied.  Messrs.  Negretti  and  Zambra  have  invented  a  thermometer,  the  construction  of 
which  is  as  follows  :  a  small  piece  of  glass  is  inserted  in  the  bend,  near  the  bulb  and  within  the  tube,  which 
it  nearly  fills :  at  an  increase  of  temperature,  the  mercury  passes  this  piece  of  glass ;  but  on  a  decrease  of 
heat,  not  being  able  to  recede,  it  remains  in  the  tube,  and  thus  indicates  the  maximum  temperature.  After 
reading,  it  is  easily  adjusted.  Pour  of  these  instruments  I  have  had  at  work  for  upwards  of  a  month,  two 
in  ordinary  observations,  and  two  subject  to  severe  tests,  and  all  have  answered  admirably.  Hitherto  every 
series  of  meteorological  observations  has  been  more  or  less  broken  by  the  frequent  plunging  of  the  steel 
index  into  the  mercury,  or  becoming  otherwise  deranged.  Messrs.  Negretti  and  Zambra  have,  in  their 
Maximum  Thermometer,  supplied  a  want  long  felt."  * 

Extract  from  the  Report  of  the  Council  of  the  British  Meteorological  Society, 
read  at  a  General  Annual  Meeting  of  its  Members,  1852  : — 

"  Negretti  and  Zambra's  Thermometer,  for  the  determination  of  maximum  temperature,  is  "one  of  the 
good  results  of  the  Great  National  Exhibition,  which  proved  itself,  as  regarded  meteorological  instruments, 
a  most  useful  exponent  of  the  insufficiency  of  those  sold  to  the  general  public ;  this  Thermometer  is  the  best 
which  has  yet  been  constructed  for  maximum  temperatures,  and  particularly  for  sun  observations ;  for  as  the 
reading  is  determined  by  the  entire  mercurial  column  being  detained  at  its  highest  point  by  a  simple  con- 
trivance within  the  tube,  the  necessity  for  an  index  is  avoided,  and  with  it  the  constant  and  distressing 
recurrence  of  derangement  attendant  upon  the  employment  of  those  generally  in  use.  This  thermometer, 
constructed  and  brought  into  operation  since  the  close  of  the  Exhibition,  has  been  for  some  time  in  the 
hands  of  Members  of  the  Council,  but  only  recently  among  its  meteorological  contributors,  from  its 
having  been  esteemed  desirable  that  the  Council  should  be  well  informed,  by  actual  experiment,  ot'  the 
well-working  of  the  instrument  before  sanctioning  its  general  circulation.  Accordingly,  in  the  early  part 
of  the  year,  for  some  months  several  of  Negretti  and  Zambra's  Maximum  Thermometers  were  subjected 
by  our  Secretary  to  severe  tests,  and  as  the  results  were  highly  satisfactory,  the  Council  have  not  only 
viewed  this  instrument  as  an  addition  to  the  practical  meteorologist,  but  strongly  recommended  its  adoption  and 
general  use." 

Copj  from  the  Report  of  the    Kew  Committee   of  the    British   Association 

"  The  very  ingenious  instrument  of  Messrs.  Negretti  and  Zambra  has  one  quality,  which,  as  regards 
durability,  places  it  above  every  other  form,  of  Maximum  Thermometer,  for  when  once  well-constructed,  it  can 
never  get  out  of  order, — the  observer  having  first  satisfied  himself  as  to  its  correctness,  may  ever  after- 
wards use  it  with  confidence,  relying  that  his  register  will  not  be  interrupted  by  any  of  those  annoyances 
to  which  he  may  have  been  accustomed  in  other  forms  of  this  instrument." 

From  E.  J.  LOWE,  Esq.,  F.R.A.S.,  F.G.S.,  &c.,  &c.,  to  Messrs.  NEGRETTI 

"  GENTLEMEN, — It  affords  me  the  greatest  pleasure  in  being  enabled  to  speak  with  praise  regarding 
your  Patent  Maximum  Thermometer.  I  have  used  a  dozen  of  them  for  some  time  at  both  my  observatories, 
and  of  these  several  since  the  date  of  their  invention.  In  no  single  instance  has  there  been  any  cause 
of  complaint.  Within  the  last  few  months  I  have  carefully  tested  them  in  various  ways,  yet  always 
with  the  most  satisfactory  results.  I  can  therefore  say  with  truth  that  your  patent  instrument  is  the  best 
Self- Registering  Maximum  Thermometer  which  has  ever  passed  through  my  hands;  indeed,  no  observer 
can  do  without  it." 


FIG.  41. 

49.     Negretti  and  Zambra's  Patent  Solar  Radiation  Thermometer 
(fig.  41). — Consists  of  a  mercurial  thermometer  with  a  blackened  bulb,    the 

*  The  thermometers  have  now  been  used  with  equal  satisfaction  for  thirty-five  years. 

45,  CORNHILL,  E.G.,  AND  122,  REGENT  STREET,  W.,  LONDON. 

FIG.  42. 

scale  is  engine-divided  on  the  stem,  and  the  divisions  protected  by  a  glass 
shield.  In  use,  it  should  be  placed  horizontally,  with  its  bulb  in  the  full 
rays  of  the  sun,  resting  on  grass,  and,  if  possible,  so  that  lateral  winds  should 
not  strike  the  bulb.  The  directions  for  use  are  identical  with  those  for  the 
determining  of  the  temperature  of  the  air.  Fig.  No.  41.  Price,  £1  10 

50.  Vacuum  Solar  Radiation  Thermometer  (fig.  42). — This  instrument 
consists  of  Negretti  and  Zambra's  blackened  bulb  Radiation  Thermometer, 
enclosed  in  a  glass  tube  and  globe,  from  which  all  air  is  exhausted,  as  suggested 
by  Sir  John  Herschel  in  the  Admiralty  Manual  of  Scientific  Enquiry,  in  1849. 
Thus  protected  from  the  loss  of  heat  which  would  ensue  if  the  bulb  were 
exposed,  its  indications  are  from  20°  to  30°  higher  than  when  placed  side  by 
side  with  a  similar  instrument  with  the  bulb  exposed  to  the  passing  air.  At 
times  when  the  air  has  been  in  rapid  motion,  the  difference  between  the  reading 
of  a  thermometer  giving  the  true  temperature  of  the  air  in  the  shade,  and  an 
ordinary  solar  radiation  thermometer,  has  been  20°  only,  whilst  the  difference 
between  the  air  temperature  and  the  reading  of  a  radiation  thermometer  in 
vacuo  has  been  as  large  as  50°.  It  is  also  found  that  the  readings  are  almost 
identical  at  distances  from  the  earth  varying  from  six  inches  to  eighteen  inches. 
By  the  use  of  this  improved  Solar  Radiator  the  amounts  of  solar  radiation  at 
different  places  are  rendered  comparable ;  with  the  exposed  bulb  Thermometer, 
(fig.  41)  the  results  could  not  be  compared,  as  the  bulbs  of  the  thermometers 
would  be  under  very  different  conditions  as  to  exposure  and  currents  of  air. 
This  new  arrangement  gives  the  readings  very  much  more  uniform,  and  is 
found  to  be  a  decided  improvement.  Price,  £150 

Instructions  for  use  same  as  No.  48. 

FIG.  43, 



51.  Negretti     and     Zambra's     Patent     Registering      Maximum 
Thermometer  with  either  black  or  bright  bulbs  for  experiments  on  radiant  or 
reflected  heat,  the  scale  divided  on  the  stem,  mounted  on  a  brass  stand. 

Fig.  43.     Price,  £1  10    0 

52.  Negretti  and  Zambra's  Improved  Solar  Radiation  Vacuum 
Thermometer,  with  Mercurial  Test  Gauge.     (Fig.  44.) 

For  some  many  years  most  important  investigations  have  been  in  progress 
in  connection  with  Solar  Heat,  and  as  it  is  evident  that  all  such  inquiry  should 

be  carried  out  with  the  utmost  precision,  a 
question  arose  as  to  the  perfection  of  the 
vacuum  in  different  Solar  Radiation  Ther- 
mometers, and  hence  a  ready  means  of  testing 
these  instruments  became  desirable  for  the 
purposes  of  comparison. 

Although  this  want  had  been  repeatedly 
pointed  out,  no  attempt  had  been  made  to 
remedy  the  defect.  At  last,  we  produced  a 
Solar  Radiation  Thermometer  with  a  small 
mercurial  vacuum  gauge  inside  the  outer 
covering,  which  gives  the  exact  amount  of 
vacuum,  or,  it  might  more  properly  be  called, 
the  exact  amount  of  air  left  in  the  space  around 
the  thermometer.  The  insertion  of  this  small 
test  gauge  in  the  manner  that  it  has  been 
effected,  is  one  of  the  most  beautiful  arrange- 
ments ever  effected  by  the  skill  of  the  glass- 
blower.  As  a  matter  of  course,  having  pointed 
out  the  road,  other  tests  were  devised.  Among 
others,  an  electrical  test,  by  inserting  metal 
wires  and  connections  in  the  two  ends  of  the 
glass  shield,  by  which  a  current  of  electricity 
from  a  Rhumkorf 's  Induction  Coil  can  be  passed 
through  the  tube,  and  the  colour,  &c.,  &c.,  of  the  electric  discharge  be  observed. 
This  test  has  two  defects,  viz.,  that  coils  and  batteries  are  not  always  available, 
and  also  that  the  metal  connections  in  the  glass  tube  are  very  liable  to  fracture, 
and  consequent  leakage  of  air  into  the  tubes  from  the  cracking  of  the  glass 
around  the  wires. 

We  need  hardly  observe  that  this  is  a  most  important  invention  and 
improvement,  for,  without  satisfactory  evidence  of  the  perfection  of  the 
vacuum,  strict  experiment  cannot  be  carried  out.  Price,  £1  16  0 

53.  Wood    Stand  for   Negretti  and    Zambra's     Patent  Vacuum 
Solar  Radiation   Thermometer,  for  experiments  at    four   feet  from    the 

FIG.  44. 

45,    COBNH1LL,   E.G.,   AND    122,    REGENT    STREET,   W.,    LONDON. 


FIG.  47. 

FIG.  46. 

FIG.  45. 

ground.  Suggested  and  recommended  by  the  Rev.  F.  W.  Stow,  who  advises 
that  the  bulb  end  of  the  thermometer  should  be  placed  facing  the  S.E.,  and  in 
such  a  manner  that  the  air  may  circulate  freely  round  it.  Strict  shade 
temperature  should  also  be  noted  by  a  good  Thermometer,  so  as  to  obtain 
the  Maximum  in  sun  and  shade,  and  from  these  the  amount  of  Solar  Radiation 
may  be  deduced.  Fig.  45.  Price,  £110 

54.  Fig.  46  shows  a  new  arrangement  of  Negretti  and  Zambra's  Patent 
Solar  Radiation  Maximum  Thermometer   in  vacuo.     It  will  be    seen   in  the 
woodcut  that  the  bulb  of  the  Thermometer  is  exposed  to  the  sky  in  a  vertical 
position,  with  its  stem  enclosed  by  a  light  case  or  box.      The  scale  is  on  the 
stem  of  the  Thermometer,   but,  as  in  No.   57  the  scale  is  figured  the  reverse 
of  an  ordinary  instrument,  the  reading  commencing  from  the  end  of  the  tube 
and  not  at  the  bulb.     This  arrangement  has  been  introduced  by  N.  and  Z.  to 
meet  some  requirements  in  connection  with  observations  on  solar  temperatures 
where   it   has   been  supposed  that  a  perfect  sphere  presented  to  the  solar  rays 
would  give    far  more    accurate   indications   than  a   projecting  bulb   such  'as 
seen  in  figs.  41  and  43.  Fig.  46.    Price,  £1  15    0 

55.  Negretti      and      Zambra's      Patent      Registering      Clinical 
Thermometers  of  various  sizes  and  forms  will  be  described  in  future  sections 
with  prices  and  illustrations. 

56.  Babinet's  Apparatus,  Sling  Thermometer  or  Thermometer  Fronde, 
for  ascertaining  the  temperature  of  the  Air  by  the  rapid  rotation  of  two  sensitive 
Thermometers,     Price  with  Thermometers.     (Fig.  47.)     £2  10s. 



57.  Negretti  and  Zambra's  Patent  Self-Registering 
Maximum  Thermometer,  for  recording  the  Temperature 
of  Mines,  Thermal  or  Boiling  Springs,  Atmospheric  or  Earth 
Temperature,  &c.,  &c. 

This  Thermometer  has  its  scale  divided  and  figured 
upon  the  stem,  the  REVERSE  of  an  ordinary  Thermometer — 
the  reading  commencing  from  the  end  of  the  tube  and  not  at 
the  bulb.  The  stem  or  tube  is  mounted  in  and  protected  by 
a  stout  glass  shield,  the  bulb  of  the  Thermometer  being 
uppermost,  and  all  mercury  passing  the  bend  or  contraction 
in  the  tube  will  by  gravity  fall  to  the  opposite  end,  and 
be  detained  and  measured.  The  whole  instrument  is 
conveniently  mounted  in  a  round  copper  or  brass  case,  with 
a  handle  or  ring  attached  to  the  top  for  suspending  the 
Thermometer.  Fig.  48. 

FIG.  48. 

FIG.  49. 

In  use,  the  Instrument  is  suspended  by  the  ring 
attached  to  the  top  of  the  metal  mounting,  and  as  it  enters  a 
heated  atmosphere  the  mercury  in  the  bulb  expands  into  the 
tube,  passing  the  bend  or  contraction*  near  the  bulb ; 
whatever  quantity  of  mercury  passes  the  bend  will  remain  in  the  tube,  and 
not  recede  when  the  temperature  cools ;  should  thirty  or  forty  degrees  of  mercury 
pass,  it  will  of  its  own  weight,  fall  to  the  end  of  the  tube ;  should  it  not  do  so, 
hold  the  Thermometer  in  an  oblique  position,  the  bulb  end  being  lowest  so  that 
the  mercury  in  the  tube  may  very  gradually  descend  until  it  touches  any 
mercury  at  the  bend,f  if  now  the  bulb  end  be  raised  the  mercury  will  again 
descend  carrying  with  it  any  small  particles  that  have  passed  the  bend- 
When  the  mercury  has  all  been  collected  at  the  end  of  tube,  read  off  in  degrees 
on  the  thermometer  scale  its  indication,  and  that  will  be  the  Maximum 

To  re-set  the  Thermometer  hold  it  bulb  downwards,  and  swing  it  back- 
wards  and  forwards,  to  force  back  the  excess  of  mercury,  beyond  the  present 
temperature,  into  the  bulb.  This  precaution  should  always  be  observed 
before  commencing  to  take  an  observation. 

Price,  in  Strong  Metal  Mountings.     £1  10    0 

57*.  In  our  Section,  "  Thermometers  for  Special  Purposes,"  will  be  found 
woodcuts  of  several  other  forms  of  these  Instruments,  with  details  as  to 
their  construction  and  use,  and  of  fig.  49,  for  obtaining  the  temperature  of 
Springs  or  Wells  or  Earth  Temperatures,  see  also  No.  46. 

*  Sometimes  a  bend  and  sometimes  a  contraction  is  used  to  separate  the  indicating  mercurial  column, 
t  The  tube  should  not  be  held  upright,  or  portions  of  the  mercury  may  pass  by  the  bend  into  the  bulb. 

45,    CORNHILL,    B.C.,   AND    122,    REGENT   STEEET,    W.,    LONDON. 

The  following  extract  from  the  Fourth  Report  of  the  Committee  on  Under- 
ground Temperature,  British  Association  for  Advancement  of  Science,  1871, 
will  sufficiently  prove  the  advantages  of  Negretti  and  Zambra's  Patent 
Maximum  Thermometer  without  further  comment : — - 

"  The  Thermometer  which  the  Committee  have  been  employing  for  the  last  three  years 
is  a  Phillips's  Maximum,  having  so  fine  a  bore  that  the  detached  column  of  mercury  which 
serves  as  the  index  is  sustained  in  the  vertical  position  by  capillary  action,  and  will  bear 
a  moderate  amount  of  shaking  without  slipping  down.  Numerous  instances,  however,  have 
occurred  in  which  the  index  has  slipped  in  consequence  of  jerks  or  concussions  sustained  by 
the  thermometer  in  hauling  it  up  from  a  depth.  During  the  past  six  months  the  Secretary 
has  been  in  correspondence  with  Messrs.  Negretti  and  Zambra  respecting  a  proposed  modifi- 
cation of  the  Maximum  Thermometer  known  by  their  name,  which  occurred  to  him  more 
than  a  year  ago,  and  was  described  by  him  privately  to  some  meteorological  friends  at  the 
last  Meeting  of  the  Association.  It  was  then  supposed  to  be  new,  but  it  now  appears  that 
Messrs.  Negretti  and  Zambra  have  made  something  of  the  kind  for  the  last  fifteen  years. 
Several  changes,  however,  were  necessary  before  the  thermometer  was  adapted  to  the  uses 
of  the  Committee,  and  the  first  complete  instruments  were  received  in  June  last.  They  are 
enclosed,  like  the  thermometers  previously  used,  in  hermetically  sealed  tubes,  for  protection 
against  pressure,  and  they  have  the  advantages  (1)  of  Icing  able  to  bear  severe  jolts  without 
derangement  of  their  indications,  and  (2)  of  presenting  to  view  a  mucli  broader  column  of 
mercury,  so  as  to  be  more  easily  read  in  a  dim  light. 

58.  Mercurial     Thermometer,    with    large     Cup 
shaped  Bulb,    (fig.  50),  convex  on  the  one  side  and  concave 
on    the    other,     exposing  a   very   large   surface,    suited   for 
experiment  on  Radiant  or  Accumulated  heat. 

Price,  Engine-divided  on  the  Stem        £150 

59.  Negretti     and     Zambra's     Patent      Marine 
Maximum  Thermometer,   (fig.  48.)     As  all  other  marine 
thermometers    are  liable  to  give  false  indications  from  the 
movements  of  the  vessel  in  rough  weather,  this  instrument 
becomes  a  most  important  improvement.    It  is  constructed  and 
used  in  a  similar  manner  to  No  57,  the  bulb  of  the  thermometer 
being   uppermost;   and  no  oscillation,   however  violent,  can 
disturb  the  indications.     It  is  mounted  in  a  strong  wood  or 
metal  frame,  suitable  for  sea  service.  Price,  £110 

60.  Helio-Pyrometer.  Mr.  T.  Southall,  of  Birmingham, 
has  published  some    very  remarkable  results  obtained   with 
a    Standard  Maximum  Registering  Thermometer,    having  a 
Blackened  Bulb  placed  within  a  shallow  box  lined  through- 
out with  black  velvet,  and  having  a  soft  cushion  of  the  same 
material  in  the  bottom.     Upon  this  cushion  the  Thermometer 

is  to  be  placed,  and   covered  over  as  closely  as  possible  by  a  piece  of  plate 
glass.     Thus  arranged,  Accumulated  Sun  Temperatures  have  been  noted   by 

FIG.  50. 


Mr.  Southall  varying  from  216  to  nearly  232  degrees  of  temperature.  In 
fact  Mr.  S.  states  he  has,  with  this  apparatus,  caused  Water  to  loil  rapidly  by 
Solar  Heat. 

Negretti  and  Zambra's  Patent  Maximum  Thermometer  will  be  found 
eminently  suited  for  experiment  with  the  Helio-Pyrometer,  as  there  is  no  fear 
of  the  thermometer  being  spoilt  by  derangement  of  the  index,  as  is  the  case 
with  both  Rutherford's  and  Phillips's  instruments. 

Price  of  complete  Apparatus  with  N.  and  Z.'s  Patent  Maximum  Thermometer     £220 
Extract  from  the  Report  of  the  Council  of  the  British  Meteorological  Society, 
read  at  a  General  Annual  Meeting  of  its  Members,  1852  : — 

"  Negretti  and  Zambra's  Thermometer,  for  the  determination  of  maximum  temperature,  is  one  of 
the  good  results  of  the  great  National  Exhibition,  which  proved  itself,  as  regarded  meteorological 
instruments,  a  most  useful  exponent  of  the  insufficiency  of  those  sold  to  the  general  public  ;  this 
Thermometer  is  the  best  which  has  yet  been  constructed  for  Maximum  temperature, 
and  particularly  for  Sun  observations. 

FIG.  51. 

FIG.  52. 

61.  Pyrheliometer  (Pouillett's)  (fig.  51),  for  ascertaining  the  effect  of 
the  sun's  heat  upon  a  given  area  by  the  number  of  degrees  of  heat  imparted 
to  mercury  in  five  minutes.  Price,  £550 

This  instrument  is  composed  of  a  shallow  cylinder  of  steel,  A,  fig.  51, 
which  is  filled  with  mercury.  Into  the  cylinder  a  thermometer,  D,  is  introduced, 
the  stem  of  which  is  protected  by  a  piece  of  brass  tubing.  We  thus  obtain 
the  temperature  of  the  mercury.  The  flat  end  of  the  cylinder  is  to  be  turned 
towards  the  sun,  and  the  surface,  B,  thus  presented  is  coated  with  lamp  black. 

45,    CORNHILL,    E.G.,   AND   122,    BEGENT   STEEET,   W.,    LONDON.  45 

There  is  a  collar  and  screw,  C,  by  means  of  which  the  instrument  may  be 
attached  to  a  stake  driven  into  the  ground,  or  into  the  snow,  if  the  observations 
are  made  at  considerable  heights.  It  is  necessary  that  the  surface  which 
receives  the  sun's  rays  should  be  perpendicular  to  the  rays ;  and  this  is  secured 
by  appending  to  the  brass  tube,  which  shields  the  stem  of  the  thermometer,  a 
disk,  ^7,  of  the  same  diameter  as  the  steel  cylinder.  When  the  shadow  of  the 
cylinder  accurately  covers  the  disc,  we  are  sure  that  the  rays  fall,  perpendicular, 
on  the  blackened  surface  of  the  cylinder. 

"  The  surface  on  which  the  sun's  rays  here  fall  is  known ;  the  quantity  of 
mercury  within  the  cylinder  is  also  known  ;  hence  we  can  express  the  effect 
of  the  sun's  heat  upon  a  given  area,  by  stating  that  it  is  competent,  in  five 
minutes,  to  raise  so  much  mercury  so  many  degrees  in  temperature." — Dr. 
TyndaWs  il  Seat  considered  as  a  Mode  of  Motion" 

62.  JSthrioscope  (Leslie's)  (fig.  52.)  The  celebrated  philosopher,  Sir 
John  Leslie,  was  the  inventor  of  this  instrument,  the  purpose  of  which  is  to 
give  a  comparative  idea  of  the  radiation  proceeding  from  the  surface  of  the 
earth  towards  the  sky.  It  consists,  as  represented  in  fig.  52,  of  two  glass  bulbs 
united  by  a  vertical  glass  tube,  of  so  fine  a  bore  that  a  little  coloured  liquid 
is  supported  in  it  by  its  own  adhesion,  there  being  air  confined  in  each  of  the 
bulbs.  The  bulb,  J.,  is  enclosed  in  a  highly  polished  brass  sphere,  D.  The 
bulb,  B,  is  blackened  and  placed  in  the  centre  of  a  metallic  cup,  C,  which  is 
well  gilt  on  the  inside,  and  which  may  be  covered  by  a  top,  F.  The  brass 
coverings  defend  both  bulbs  from  solar  radiation,  or  any  adventitious  source 
of  heat.  When  the  top  is  on,  the  liquid  remains  at  zero  of  the  scale.  On 
removing  the  top  and  presenting  the  instrument  to  a  clear  sky,  either  by  night 
or  by  day,  the  bulb,  B,  is  cooled  by  terrestrial  radiation,  while  the  bulb,  A, 
retains  the  temperature  of  the  air.  The  air  confined  in  B,  therefore,  contracts ; 
and  the  elasticity  of  that  within  A  forces  the  liquid  up  the  tube,  to  a  height 
proportionate  to  the  intensity  of  the  radiation.  Such  is  the  sensitiveness  of 
the  instrument,  that  the  smallest  cloud  passing  over  it  checks  the  rise  of  the 
liquid.  Fig.  52.  Price,  £1  10  0 


FIG.  53. 

63.  Negretti and  Zambra's Standard  Minimum  Thermometer.  (Fig. 
53.)  consists  of  an  enamelled  glass  tube,  the  bulb  and  parts  of  the  bore  of  which 
is  filled  with  perfectly  pure  colourless  Spirits  of  Wine,  in  which  floats  freely  a 



black  glass  index.     The  tube  is  engine  divided  and  mounted  as  shown  in  fig.  53. 
on  either  N.  and  Z.'s  patent  Porcelain  or  Opal  Glass  Scales. 

Directions  for  using  Minimum  Thermometers,  for  the  Determination  of  the 
Minimum  Temperature  of  the  Air. — Having  caused  the  black  index  to  flow  to 
the  end  of  the  column  of  spirit,  by  slightly  tilting  the  Thermometer,  bulb 
uppermost,  suspend  the  instrument,  (in  the  shade  with  the  air  passing  freely  to 
it  on  all  sides)  by  the  two  plates  attached  for  that  purpose, — in  such  manner 
that  the  bulb  is  about  half  an  inch  lower  than  the  end  of  the  Thermometer 
furthest  from  the  bulb, — then  on  a  decrease  of  temperature,  the  spirit  will 
descend,  carrying  with  it  the  index  towards  the  bulb ;  on  an  increase  of 
temperature,  the  spirit  will  ascend  in  the  tube  beyond  the  index,  leaving  that 
end  of  the  index  furthest  from  the  bulb  indicating  the  extreme  of  cold  or 
Minimum  temperature.  To  re-set  the  instrument,  simply  raise  the  bulb  end  of 
the  Thermometer  a  little,  as  before  observed,  and  the  index  will  again  descend 
to  the  end  of  the  spirit,  ready  for  future  observation. 

Price,  in  mounting  as  fig,  53     £1     1     0 

FIG.  54. 

64.  Negretti  and  Zambra's  Standard  Terrestrial  Radiation 
Thermometer,  (fig.  54).— The  bulb  of  this  instrument  is  transparent,  with  the 
divisions  engraved  on  its  stem  similar  to  that  for  solar  radiation.  In  use,  to  be 
placed  with  its  bulb  fully  exposed  to  the  sky,  resting  on  grass,  with  its  stem 
supported  by  little  forks  of  wood.  Price,  £110 

FIG.  55. 

65.  Negretti  and  Zambra's  Link  shaped  Bulb  Minimum 
Thermometer,  mounted  either  as  a  Terrestrial  Radiation  irstrument,  fig.  55,  or 
on  a  Porcelain  scale  as  fig.  53.  This  peculiar  form  of  bulb  was  devised  by  Negretti 
and  Zambra  to  obtain  extreme  sensitiveness  by  the  large  surface  exposed  to  air. 

Price,    £150 

45,   CORNHILL,    E.G.,   AND    122,    REGENT   STREET,    W.,    LONDON. 


FIG.  57. 

FIG.  56. 

Brass    Stand   for  use   with 
Price,    5s.  6d. 

66.  Negretti   and    Zambra's   Minimum   or   Terrestrial  Radiation 
Thermometer  with  Brass  Stand,     (fig.  56).  Price,    £150 

67.  Concave    Metallic    Reflector  on    a 
Terrestrial  Radiation  Thermometer  (fig.  57). 

N.B. — As  Alcohol  Thermometers  have  a  tendency  to  read  lower  by  age, 
owing  to  the  volatile  nature  of  the  alcohol  allowing  particles  in  the  form  of 
vapour  to  rise  and  lodge  in  the  tube,  it  becomes  necessary  to  compare  them 
occasionally  with  a  Mercurial  thermometer  whose  index  error  is  known ;  and 
if  the  difference  be  more  than  a  few  tenths  of  a 
degree,  examine  well  the  upper  part  of  the  tube  to  see 
if  any  alcohol  is  in  the  bore,  if  so,  detached  por- 
tions can  be  joined  to  the  main  column  by  swinging 
the  thermometer  sharply  backwards  and  forwards 
with  a  pendulous  motion,  keeping  the  bulb  down- 
wards. When  all  the  detached  portions  are  joined, 
allow  it  to  stand  upright  for  an  hour  before  again 
suspending  it  for  observations. 

68.  Negretti  and  Zambra's  Patent 
Mercurial  Minimum  Thermometer,  represented 
by  fig.  58,  has  a  cylindrical  bulb  of  large  size.  The 
reason  for  having  the  bulb  large  is  to  allow  the 
internal  diameter  of  the  thermometer  tube  to  be 
greater  than  that  generally  used  for  thermometrical 
purposes,  so  that  a  steel  index,  pointed  at  both 

ends,  may  move  freely  within  when  required. 

FIG.  58*.' 

In  use,  the  Thermometer  is  suspended  perpendicularly  with 
the  steel  index  resting  on  the  surface  of  the  mercurial  column. 
As  the  mercury  in  the  cylinder  contracts  from  the  effect  of 
cold,  that  in  the  tube  descends,  and  the  index,  of  its  own  gravity, 
follows  it ;  on  the  contrary,  as  the  mercury  expands  and  rises 
in  the  tube,  it  passes  the  index  on  one  side,  and  in  rising, 
exerts  a  lateral  pressure  on  the  needle,  and  jambs  it  to  one  side 
of  the  tube,  where  it*  remains  firmly  fixed,  leaving  the  upper 

FIG.  58. 


point  of  the  needle  indicating  the  minimum  temperature.  In  this  thermometer 
the  reading  is  always  from  the  upper  point  of  the  needle,  and  not  from  the 
mercury  itself. 

To  extricate  the  needle  from  the  mercury,  a  magnet  is  used,  when,  if  the 
needle  is  embedded  only  a  few  degrees,  it  can  readily  be  withdrawn  without 
altering  the  position  of  the  instrument.  Should  the  magnet  not  be  sufficient 
for  the  purpose,  we  simply  turn  the  thermometer  from  the  upright  position, 
slightly  elevating  the  bulb  (58*2).  The  mercury  and  index  will  then  flow 
into  the  small  reservoir  (58®).  Should  the  index  not  freely  leave  the  tube  with 
the  mercury,  assist  it  with  a  magnet  and  when  the  mercury  and  index  are 
in  the  upper  bulb  (58*2),  apply  a  magnet  outside,  which  will  attract  and  hold 
fast  the  index ;  and  whilst  thus  holding  it,  again  bring  the  thermometer  to  the 
upright  position,  when  the  mercury  will  immediately  fall  back  into  the  tube, 
leaving  the  index  attached  to  the  magnet  (fig.  4),  with  which  it  is  guided 
down  to  the  surface  of  the  mercury,  ready  for  another  observation. 

Price,     £2  10    0 

The  value  of  these  instruments  may  be  estimated  from  the  following  letters, 
received  from  gentlemen  by  whom  the  thermometers  have  been  tested  since 
their  invention. — 

LEWISHAM,  1856,  February  27. 

"  GENTLEMEN,— In  reply  to  your  note  just  received,  I  beg  to  say  that  your  new  Mercurial  Minimum  Ther- 
mometer was  suspended  by  the  side  of  two  Minimum  Thermometers  of  the  best  kind  of  the  ordinary  con- 
struction, on  the  day  I  received  it  from  you,  viz.,  1855,  November  21,  and  it  has  been  examined  and  read 
every  day  since,  during  which  interval  of  time  the  temperature  has  varied  from  15°  to  60°.  It  has  acted 
equally  well  within  this  range.  In  the  course  of  the  experiments,  it  was  found  that  at  times  differences 
amounting  to  2°  and  3°  existed  in  the  minimum  readings  between  those  of  the  new  mercurial  and  old 
spirit  thermometers.  These  differences  were  found  due  to  two  causes.  The  one  occurred  at  low 
temperatures,  and  on  reference  to  independent  registers,  it  was  found  that  the  readings  of  the  mercurial 
were  right,  the  difference  being  attributable  to  the  sluggishness  of  the  alcohol;  and,  in  the  other  case,  it 
was  found  that  the  index  of  the  ordinary  thermometer  had  unduly  moved  towards  the  bulb,  the  instru  - 
ment  having  been  shaken  by  the  wind. 

"I  consider  the  new  Minimum  Thermometer  a  very  important  addition— indeed  a  more  important  one 
than  the  Maximum  Thermometer  of  your  invention,  as  by  its  means  we  can  register  all  observations  of 
temperature  by  the  use  of  one  fluid,  and  that  the  recognised  standard  for  the  measurement  of  heat. 

"With  respect  to  your  Maximum  Thermometer,  it  acts  admirably,  and  leaves  scarcely  anything  to  be 
desired.     It  has  never  been  out  of  order  during  the  four  years*  I  have  had  it  in  constant  use,  and  it  does 
not  seem  possible  to  put  it  out  of  order,  except  by  the  destruction  of  the  instrument. 
"  I  am,  Gentlemen,  your  obedient  Servant, 

"  Messrs.  NEGRETTI  and  ZAMBRA,  Opticians."  "  Secretary  to  the  British  Meteorological  Society. 

The  following  is  an  extract  from  a  letter  to  the  inventors,  Messrs.  NEGRETTI 
and  ZAMBRA,  from  E.  J.  LOWE,  Esq.,  dated  Observatonj,  Beestrm,  near  Nottingham : 

"Your  Patent  Mercurial  Thermometer  is  an  admirable  invention.  I  have  worked  it  to  my  entire 
satisfaction.  I  have  tested  its  usefulness  in  many  different  ways,  every  one  of  which  has  been  perfectly 
satisfactory.  It  is  certainly  a  meteorological  triumph  for  which  meteorologists  must  return  you  thanks." 

Care  must  be  taken  not  to  withdraw  the  magnet  until  the  index  is  in 
contact  with  the  mercury,  for,  if  released  before  touching,  it  might  plunge  too 
deeply  and  give  a  false  indication.  The  rule  for  re-setting  it  will  be  to  bring 

*  It  is  now  more  than  twenty -nine  years,  and  still  the  thermometer  is  perfect. 

45,   CORNHILL,   B.C.,   AND    122,    EEGENT   STREET,    W.,    LONDON. 


the  needle-point  in  contact  with  the  mercury,  and  then  withdraw  the  magnet, 
having  previously  ascertained  that  no  particles  of  mercury  are  attached  to 
the  index. 

It  may  sometimes,  though  rarely,  happen  that,  from  the  time  a  minimum 
temperature  is  registered  by  the  index,  and  the  time  an  observation  is  made, 
.the  mercury  may  have  risen  so  high  in  the  tube  as  to  completely  pass  the 
index,  as  shown  (fig.  3).  Should  it  so  happen,  the  space  which  the  index 
occupies  will  readily  be  observed,  as  it  will  be  pressed  to  one  side  of  the  tube, 
causing  a  different  appearance  in  that  part,  although  the  point  of  the  needle 
may  not  be  seen.  If  such  be  the  case,  apply  a  magnet  to  the  spot  where  you 
see  the  index  is  fixed :  this  will  hold  the  needle  firmly.  Then,  by  slightly 
tilting  the  thermometer  bulb  uppermost,  the  mercury  will  flow  into  the  top 
bulb,  leaving  the  index  attached  to  the  magnet,  and  quite  uncovered.  Having 
taken  the  reading,  draw  the  needle  into  the  top  bulb,  and  hold  ifc  there  whilst 
you  adjust  the  thermometer  by  again  bringing  it  to  the  upright  position. 

So     \    70   I     £31    $9 

NEC  PETTI  &  2 AM  BRA-,     LONDON. 

FIG.  59. 

68.  Negretti  and  Zambra's  Patent  Mercurial  Minimum  Thermo- 
meter. The  Patent  Mercurial  Minimum  Thermometer  is 
constructed  as  follows :  A  is  the  thermometrical  or  indicating 
tube,  and  B  is  a  small  vertical  tube  connected  to  it  at  right  angles, 
about  one  inch  from  the  bulb.  In  the  tube  B,  at  the  point  C, 
is  inserted  a  platinum  plug,  which  does  not  entirely  fill  the 
bore,  as  may  be  seen  by  elevating  either  end  of  the  instru- 
ment, as  the  mercury  will  then  flow  in  the  tube  A,  either  to  or  from  the  bulb, 
depending  upon  which  end  of  the  thermometer  is  elevated  or  depressed. 

To  set  for  Observation,  and  use  the  Patent  Mercurial  Minimum  Thermometer. — 
Hold  the  thermometer  with  the  bulb  downwards  until  the  bulb  and  tube  B 
are  quite  full  of  mercury ;  then  raise  the  bulb  end  of  the  thermometer,  and 
the  mercury  will  flow  from  the  tube  B  into  the  tube  A,  until  it  reaches  the 
plug  C,  where  it  will  be  checked  by  the  mercury  adhering  to  the  platinum  plug 
— the  affinity  of  platinum  for  mercury  being  sufficient  to  arrest  the  flow  of 
mercury,  if  not  allowed  to  flow  too  rapidly.  Should  it  overshoot  the  mark  and 
go  to  the  end  of  the  tube  A  repeat  the  operation  more  carefully. 

Suspend  the  thermometer  horizontally,  and  on  a  decrease  of  the  tem- 
perature the  mercury  will  fall  in  the  tube  A  until  it  attains  its  minimum 


temperature ;  and  on  an  increase  of  temperature  the  mercury  will  rise  in  the 
tube  B,  leaving  the  indicating  column  in  A,  registering  the  extreme  degree  of 
cold,  or  minimum  temperature.  To  re-set  the  instrument  for  future  obser- 
vation, simply  raise  the  bulb  end  of  the  thermometer  until  the  mercury  again 
comes  in  contact,  and  is  checked,  by  the  platinum  plug. 

This  form  of  Mercurial  Minimum  Thermometer  has  one  very  great 
advantage  over  the  preceding  instrument,  viz.,  it  is  much  less  liable  to  injury 
or  breakage  in  transit.  Price,  fig.  69.  £220 

69.  Actinometer,   Sir  John  HerschelPs    (fig.  60),  for 
ascertaining  the  absolute  heating  effect  of  the  solar  rays,  in  which 
time  is  considered  one  of   the   elements   of  observation.      The 
Actinometer  consists  of  a  large    cylindrical   thermometer  bulb, 
with  a  scale.considerably  lengthened,  so  that  minute  changes  may 
be  easily  seen.     The  bulb  is  of  transparent  glass,  filled  with  a 
deep  blue  liquid,  which  is  expanded  when  the  rays  of  the  sun 
fall  direct  on  the  bulb.     To  take  an  observation,  the  Actinometer 
is  placed  in  the  shade  for  one  minute,   and  read  off,  it»is  then 
exposed  for  one  minute  to  sunshine,  and  its  indication  recorded  ; 
it  is  finally  restored  to  the  shade,  and  its  reading  noted.     The 
mean  of  the  two  readings  in  the  shade,  subtracted  from  that  in 
the  sun,  gives  the  actual  amount  of  expansion  of  the  liquid  pro- 
duced by  the    sun's  rays  in  one  minute  of  time.      For  further 
information    see    "  Report  of  the  Royal  Society  on   Physics  and 
Meteorology."  Price,  £770 

70.  Negretti  and  Zambra' s  improved  Isolated  Glass 
Mountings  for  protecting  Thermometer  Scales  from  moist- 
ure.    Many  observers  having  found  much  trouble  in  reading  the 
indications  of  Terrestrial  Radiation  and  exposed  Thermometers 
from  the  condensation  of  moisture  on  the  inside  of  the  protect- 
ing  glass  tubes  or  shields,  Messrs.  Negretti  and  Zambra  have 
succeeded  in  perfecting  a  method  of  mounting  up  such  instru- 
ments that  quite  obviates  the  difficulty.     This  improvement  con- 
sists in  so  melting  an  external  glass  cylinder  round  both  ends 
of  the  thermometer  as  to  render  the  shield  perfectly  air-tight,  in 
fact,  to  hermetically  seal   up  the  instrument  in  it — so  that   no 
moisture  can  possibly  accumulate  inside  the  tube,  whilst  the  bulb 

FIG  60          °^    *^e  thermometer  is  perfectly  exposed  to  the  air. 

Negretti  and  Zambra  are  now  applying  this  improvement  with 
great  advantage  to  Thermometers,  Hygrometers,  and  many  other  instruments 
required  for  out  of  door  exposure.  These  isolating  mountings  will  make 
a  slight  addition  to  the  cost  -of  such  Thermometers. 

45,    COBNHILL,    B.C.,    AND    122,    KEGENT    STREET,    W.,    LONDON.  51 

FIG.  61. 

71.  Portable  Patent  Maximum  and  Minimum  Registering  Thermo- 
meters.— Negretti  and  Zambra's  Small  Patent  Maximum  and  Minimum 
Registering  Pocket  Thermometers,  fitted  into  a  secure  and  convenient 
pocket  case,  special  for  travellers,  (fig.  61.)  Price  .  .  .  .£220 

Larger  Standard  size  ditto      2  10    0 

The  construction  and  use  of  the  Portable  Registering  Thermometers  is 
identical  with  N.  and  Z.'s  larger  Standard  instruments,  Nos.  40  and  53.  These 
are  the  only  Registering  Thermometers  that  will  travel  without  dera-ngement. 
Explicit  printed  instructions  for  use  accompany  each  set. 

72.  Marie  Davy's  Actinometer,  consisting  of  two  Thermometers 
in  vacuo,  one  with  a  bright  and  the  other  with  a  black  bulb,  both  divided  on  the 
stems  and  mounted  upon  a  suitable  stand  for  out-door  exposure.  Price,  £330 

To  convert  Fahrenheit  readings  to  Centigrade. 

Subtract  32  and  multiply  the  remainder  by  - 


e.g.  68°  P.=(  68— 32)x-  =  20°  C. 

To  convert  Fahrenheit  readings  to  Reaumur. 

Subtract,  32  and  multiply  the  remainder  by  - 

e.g.  68°  F.=(  68— 32)  X  -  =  16°  R. 

To  convert  Centigrade  readings  to  Fahrenheit. 

Multiply  by  f  and  add  32. 

To  convert  Reaumur  degrees  to  Fahrenheit. 
Multiply  by  |  and  add  32. 

To  convert  Centigrade  to  Reaumur. 

Multiply  by    - 

To  convert  Reaumur  to  Centigrade. 
Multiply  by  | 

NOTE.— All  of    Negretti  and   Zambra's   Standard  Thermometers  may  be  had  with. 
Centigrade  or  Reaumur  Scales  to  order. 








FIG.  62. 

73.  Negretti  and  Zambra's  Patent  Atmospheric  Eecording 
Thermometer  (fig.  62).  For  any  hour  determined  upon,  the  clock 
carrying  the  Thermometer  is  -set  (similar  to  an  alarum  clock),  and 
when  the  hands  arrive  at  this  point  of  time,  the  movement  of  the 


clock. releases  a  catch  or  detent,  and  the  Thermometer*  with  its  scale  is 
revolved,  the  mercury  then  records  the  temperature  of  the  air  for  that 
exact  moment  in  a  similar  manner  to  those  mentioned  in  the  next  page. 
These  Recording  Instruments  are  found  to  be  a  most  important  addition  to 
our  Meteorological  Instruments,  and  no  slight  boon  to  observers  in  many 
parts  of  the  world  who  are  engaged  in  taking  simultaneous  observations 
with  our  own  at  fixed  hours.  ~ Price,  as  fig.  62.  £440 

*  The  Thermometer  used  with  this  apparatus  is  shown  ly  fig.  62a,  and  is  fully  described  on  page  53. 

45,   CORNHILL,   B.C.,   AND    122,   REGENT   STREET,   W.,    LONDON.  53 



An  instrument  for  obtaining  automatic  thermometer  readings 
at  stated  intervals  of  time  having  long  been  sought  for — after  many 
experiments,  NEGRETTI  &  ZAMBRA  have  invented  and  constructed  one 
both  simple  and  accurate. 

74.  Negretti  &  Zambra's  Patent  Hourly  Recording 
Thermometrical  Apparatus.  This  new  instrument  consists  of 
twelve  Thermometers,  mounted  on  a  suitable  stand,  a  good  Clock, 
and  a  Galvanic  Battery.  The  advantages  are — simplicity  of 
manipulation,  both  in  taking  the  recorded  readings  and  setting  the 
thermometers  for  future  observations ;  the  most  important  one,  being 
able  to  expose  the  thermometers  at  any  distance  from/  the  clock  and 
battery — the  only  limit  being  the  length  of  the  conducting  wires 
and  the  strength  of  the  battery. 

Before  describing  the  mechanical  and  electrical  arrangements  of 
the  apparatus,  we  proceed  to  explain  the  construction  and  action  of 
the  thermometers  themselves.  This  will  be  best  understood  by 
reference  to  the  engraving,  fig.  63. 

The  bulb  is  cylindrical,  and  Mercury  is  the  thermometrical  fluid. 
The  neck  of  the  bulb  is  contracted  at  A,  and  upon  the  shape  and 
fineness  of  this  construction  the  success  of  the  instrument  depends. 
Beyond  A  the  tube  is  bent,  and  a  small  catch  reservoir  is  formed  at  B, 
for  a  purpose  to  be  presently  explained.  At  the  end  of  the  tube  a 
small  r.eceptacle,  C,  is  provided.  When  the  bulb  is  downward  it  contains 
sufficient  mercury  to  fill  the  tube  and  a  part  of  the  reservoir,  0,  leaving  suf- 
ficient space  in  C  for  the  expansion  of  the  mercury.  In  this  position  no  scale 
would  be  possible,  as  the  apparent  movement  of  the  mercury  would  be  con- 
fined to  the  space  C.  When  the  thermometer  is  held  bulb  upward,  the 
mercury  breaks  off  at  A,  and  by  its  own  weight  flows  down  the  tube,  filling 
C  and  a  portion  of  the  tube  above  C,  in  relation  to  the  existing  temperature. 
The  scale  accordingly  is  made  to  read  upwards  from  C.  To  set  the  instrument 
for  observation,  it  is  only  necessary  to  place  it  bulb  downward,  then  the 
mercury  takes  the  temperature  just  as  an  ordinary  thermometer.  Whenever 
the  existing  temperature  is  required,  all  that  has  to  be  done  is  to  turn  the 
thermometer  bulb  upward  ;  the  mercury  will  then  break  off  at  A,  falls  to 


end  C,  and  in  this  position  the  temperature  can  be  noted.     The  engraving, 
fig.  63,  shows  the  thermometer  after  it  has  been  inverted. 

This  reading  may  be  taken  at  any  time  after  the  thermometer  has  been 
turned  over,  for  the  quantity  of  mercury  in  the  lower  part  of  the  stem,  which 
gives  the  reading,  is  too  small  to  be  sensibly  influenced  by  a  change  of  tempera- 
ture, while  that  in  the  bulb  will  continue  to  contract  with  greater  cold  and  to 
expand  with  greater  heat,  and  in  the  latter  case  some  mercury  will  pass  the 
contraction  A,  and  may  fall  down  and  lodge  at  B,  but  it  cannot  go  further  so 
long  as  the  bulb  is  upward,  and  thus  the  temperature  to  be  read  off  will  not  be 
vitiated.  It  must  be  clearly  understood  that  the  thermometer  is  only  intended 
to  give  the  temperature  at  the  time  when  it  turned  over.  The  divisions  and 
figures  are  engraved  upon  the  stem  of  these  thermometers.* 

It  will  be  seen  in  the  accompanying  drawing  that  twelve  thermometers  are 
mounted  on  the  stand  ;  each  one  is  sustained  upon  a  metal  arm  in  such  a  man- 
ner that  it  will  fall  over  and  become  inverted  by  the  release  of  a  stop  or  detent 
from  the  joint  action  of  the  clock  and  galvanic  battery. 

In  the  drawing,  six  of  the  twelve  thermometers  are  shown  inverted,  the 
bulbs  being  upwards,  the  clock  at  each  of  the  six  successive  hours  having  made 
contact  and  completed  the  galvanic  circuit,  and  by  the  action  of  an  electro- 
magnet released  the  detents,  and  allowed  the  thermometers  to  fall  over  and 
record  the  temperature  for  that  moment.  This  action  is  produced  by  simple 
mechanism  on  the  back  of  the  clock  dial,  the  contact  being  made  at  each  hour 
It  will  be  evident  that  the  thermometers  could  be  made  to  record  half-hourly, 
or  they  might,  by  increasing  the  number,  be  made  to  register  every  fifteen 
minutes,  or  less,  the  only  limit  being  the  number  of  thermometers  used. 

When  the  thermometers  are  all  reversed,  the  readings  may  be  quickly 
taken  and  the  thermometers  re-turned  to  their  original  positions,  bulbs  down- 

Attached  to  the  back  of  the  clock  dial,  and  in  its  centre,  is  a  disc  of  ebonite, 
about  two  inches  in  diameter,  with  a  hole  in  the  centre  to  allow  the  spindle  to 
pass  on  which  the  clock  hands  are  fixed.  Round  the  edge  of  this  disc  are 
twelve  platina  studs,  one  being  opposite  each  hour  on  the  clock  dial ;  each  stud 
is  separately  connected  to  one  of  twelve  terminals  in  the  order  of  1  to  12 
at  back  of  clock,  viz. :  The  stud  opposite  12  o'clock  on  the  dial  is  carried  to  No. 
12  terminal,  &c.,  &c.  Immediately  behind  the  hour  hand,  at  the  back  of  the 
dial,  and  attached  to  the  same  spindle,  is  a  metal  spring  which  touches  each 
stud  in  succession  as  the  hour  hand  travels  round.  This  spring  is  not 
insulated  from  the  metal  work  of  the  clock ;  consequently  the  current  runs  to 
the  clock. 

*  These  Thermometers  are  divided  with  either  Fahrenheit  or  Centigrade  Scales,  and  their  number  may 
be  increased  to  special  order. 

45,  COBNHIU,,  E  0.,  AND  122,  REGENT  STREET,  W.,  LONDON. 


Negretti  and  Zambra's  Patent  Apparatus  for  Recording 
Hourly  Temperatures.     (FiG.  64.) 


Fixed  at  the  back  of  the  clock  dial,  near  its  outer  edge,  are  two  little  glass 
cups  containing  mercury,  one  of  which  is  connected  to  the  metal  work  of  the 
clock ;  the  other  glass  cup  is  connected  to  the  thirteenth  terminal  on  the  back 
of  the  clock.  Immediately  over  these  two  cups,  and  fixed  to  an  arm  or  lever,  is 
a  forked  piece  of  platina  wire,  which,  when  depressed  into  the  cups,  forms  a 
connecting  bridge  from  one  to  the  other.  The  lever  is  depressed  when  one  end 
is  lifted  by  the  minute  hand  of  the  clock.  This  is  accomplished  by  means  of  a 
wedge-shaped  piece  of  steel  brought  through  to  the  front  of  the  dial,  and  acted 
upon  by  the  minute  hand  directly  over  twelve  o'clock ;  when  the  minute  hand 
approaches  twelve,  it  presses  the  left  angle  of  the  wedge  and  lifts  it. 

A  terminal  at  the  outside  of  a  box  containing  twelve  magnets  is  connected 
to  a  metal  bar  running  the  entire  length  of  the  same,  to  which  is  attached  one 
end  of  a  wire  from  each  of  the  twelve  electro-magnets  ;  the  other  ends  of  the 
wires  from  the  electro-magnets  are  separately  connected  to  the  twelve  terminals 
under  the  box  containing  the  magnets,  thence  by  separate  wires  to  the  twelve 
terminals  on  the  clock,  in  the  order  of  from  1  to  12  as  marked. 

We  will  now  suppose  the  time  to  be  six  o'clock.  The  battery  is  connected 
as  follows : — One  pole  to  the  thirteenth  terminal  on  the  clock,  the  other  pole  to 
the  terminal  at  end  of  box  on  the  Recording  apparatus.  The  electric  circuit  is 
now  complete.  From  the  battery  to  the  thirteenth  terminal  on  clock,  then  to 
one  of  the  glass  cups,  over  the  little  bridge  of  wire  to  the  other  glass  cup,  thence 
through  metal  work  of  the  clock  to  the  spring,  which  spring  touches  upon  the 
stud  at  the  back  of  the  hour  hand  (at,  say  six  o'clock),  from  thence  to  No.  6 
terminal  on  the  back  of  the  clock,  from  there  to  No.  6  terminal  under  the 
box  containing  the  electro-magnets,  through  No.  6  magnet  to  the  bar  above, 
then  to  the  terminal  at  the  end  of  the  box,  and  back  to  battery.  In  its  circuit, 
No.  6,  magnet  attracts  its  keeper,  the  catch  falls,  and  allows  No.  6  thermometer 
to  turn  over,  and  in  like  manner  throughout  the  series. 

Price,  fig  64.     £52  10    0 


75.  This  instrument  shown  by  fig.  65  consists  of  a  glass  sphere  ground 
perfectly  true,  mounted  upon  a  brass  frame,  with  suitable  adjustments  for  placing 
its  axis  parallel  with  the  axis  of  the  earth  ;  it  has  also  a  divided  semi-circle 
arranged  to  adjust  the  apparatus  for  use  in  any  latitude. 

Surrounding  one-half  of  the  glass  sphere  is  placed  a  concentric  metal  plate, 
for  holding  the  prepared  and  divided  paper  cards,  upon  which  the  record  is 
burned  by  the  concentrated  Solar  rays. 

45,  COENHILL,  E.G.,  AND  122,  BEGENT  STEEET,  W.,  LONDON.        57 

FIG.  65. 

Two  grooves  are  formed  upon  the  concentric  plate,  by  which  the  position 
of  the  divided  cards  can  be  varied  to  suit  the  elevation  of  the  sun  at  different 
seasons  of  the  year. 

In  use,  the  Sunshine  Recorder  should  be  placed  geographical  North  and 
South,  similar  to  a  sun  dial. 

Price,  fig.  65.    £12  12    0 
A  supply  of  prepared  cards  sufficient  for  one  year's  use      .        .        .        •        £1  12    0 

FIG.  66.  FIG.  67. 

76.    Jordan's  Sunshine  Recorder   (Patent),   made  and  supplied 
only  by  Negretti  and  Zambra. 



Since  the  indention  in  1853  of  Mr.  CAMPBELL'S  instrument  for  automatically 
registering  the  duration  of  Sunshine,  the  subject  has  become  of  increasing 
interest,  and  improved  forms  of  his  instrument  have  been  generally  adopted  at 
the  principal  Observatories  and  Meteorological  Stations  where  the  hours  of 
bright  Sunshine  are  regularly  observed  and  registered.  These  ingenious 
instruments  are  perfect  recorders  of  Sunshine  so  long  as  the  sky  is  clear,  but 
are  too  costly  to  come  into  general  use  by  the  greater  number  of  observers  now- 
interested  in  the  subject.  It  is  to  meet  this  difficulty  that  the  instrument  now 
introduced  has  been  designed.  We  believe  that  it  meets  all  the  requirements  ; 
it  is  accurate  in  its  action,  of  simple  construction,  and  sufficiently  cheap  to  come 
within  the  means  of  all  those  who  are  interested  in  this  comparatively  new 
branch  of  meteorological  science. 

Half  Size. 

FIG.  68. 

The  action  of  Mr.  JORDAN'S  Sunshine  Recorder  differs  entirely  from  that 
of  the  instrument  above  referred  to,  inasmuch  as  the  results  are  obtained  by 
means  of  photography,  instead  of  by  the  burning  power  of  the  concentrated 
solar  rays  ;  it  is,  however,  only  on  days  when  the  atmosphere  is  a  little  hazy,  or 
the  sun  slightly  obscured  by  thin,  filmy  cloud,  that  there  is  any  important 
difference  in  the  record  of  the  two  instruments  ;  at  such  times  the  photographic 
registering  instrument  will  probably  show  an  excess  of  sunshine,  as  under 
certain  conditions  the  thin  film  of  cloud  or  haze  interferes  more  with  the  action 
of  the  heat  rays  than  it  does  with  the  actinic  rays. 

The  new  instrument — which  is  figured  on  the  other  side — consists  of  a 
dark  cylindrical  chamber,  on  the  inner  circumference  of  which  is  placed  a 
carefully  prepared  photographic  paper.  The  ray  of  sunlight  being  admitted 
into  this  chamber  through  small  apertures  in  the  side,  is  received  on  the 
sensitized  paper  or  chart,  and  travels  around  it  by  virtue  of  the  earth's  rotation, 
leaving  a  distinct  trace  of  chemical  action,  thereby  registering  its  duration, 
and  the  degrees  of  its  intensity,  varied  by  every  passing  cloud.  The  cylinder 
is  mounted  on  a  suitable  stand,  having  simple  means  of  adjustment,  for  the 
different  seasons  of  the  year,  and  for  the  use  of  the  instrument  in  any  latitude. 

Price.  Sunshine  Recorder— Fig.  66 £330 

Ditto        — Fig.    67,   with  rackwork  adjustment  and 

clamping  screws 550 

A  Box  containing  100  prepared  CHARTS,  with  instructions- 
Fig.  68     100 

45,    COBNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  59 

The  Charts  are  printed  upon  sensitized  paper,  ruled  with  vertical  lines, 
representing  the  hours  and  minutes  of  the  day;  they  are  supplied,  ready 
for  use,  in  boxes  containing  100  each.  The  records  obtained  are  rendered 
permanent  by  simply  washing  the  papers  for  a  few  minutes  in  cold  water  and 
afterwards  drying  them  between  blotting-paper. 


77.  Select  a  suitable  position  which  has  the  full  range  of  the  sun  at  all 
seasons  of  the  year.  Provide  affirm  support  with  a  perfectly  level  top,  place  the 
Instrument  upon  it  (the  lid  of  the  cylinder  facing  north),  and  when  the  sun  is 
on  the  meridian  (12  o'clock)  turn  the  instrument  on  its  base  until  the  shadow 
of  the  pin  on  the  lid  of  the  cylinder  coincides  with  the  vertical  line  on  the 
white  glass  behind  it.  When  this  adjustment  has  been  correctly  made,  the 
instrument  may  be  permanently  screwed  down  to  its  support,  then  incline  the 
cylinder  on  its  horizontal  axis,  by  means  of  the  milled  head  at  the  side,  until 
the  point  of  the  shadow  of  the  aforesaid  pin  falls  on  the  point  of  intersection 
of  the  two  lines,  and  clamp  securely  by  means  of  the  opposite  milled  head,  the 
ray  of  sunlight  passing  through  the  central  aperture  will  then  fall  on  the 
twelve  o'clock  division  of  the  chart.  This  adjustment  will  require  to  be  altered 
occasionally  as  the  seasons  vary,  the  necessity  for  alteration  being  shown  by 
the  position  of  the  trace  above  or  below  the  central  line  of  hour  divisions  on  the 

The  charts  should  be  inserted  in  the  cylinder  each  day  after  sunset,  ready 
for  the  following  day,  the  ends  being  placed  against  the  stops  provided  for  the 
purpose.  On  removing  the  charts  from  the  instrument  after  the  day's  observa- 
tion the  number  of  hours  recorded  should  at  once*  be  tafadated,  the  trace  may 
then  be  rendered  permanent  by  immersing  the  chart  for  a  few  minutes  in  cold 
water,  until  the  surface  becomes  white  and  the  trace  a  bright  blue  colour ;  it 
should  then  be  removed  and  dried  between  blotting  paper.  Care  must  be  taken 
not  to  expose  the  sensitized  charts  to  the  daylight  longer  than  is  necessary  for 
removing  and  inserting  them  in  the  cylinder.  The  cylinder  being  held  in 
position  on  the  frame  by  a  clamping  screw  can  be  easily  removed  for  the  purpose 
of  changing  the  chart,  which  may  be  done  either  at  the  place  of  observation  or 

*  This  precaution  is  necessary  that  any  very  faint  traces  on  the  chart  may  not  be  lost 
before  registering,  by  too  long  immersion  in  water,  or  it  may  be  advisable  to  mark  with  a 
pencil  the  limits  of  the  trace  before  placing  in  water. 



78.  Deep    Sea  Sounding    Thermometers,     Self-Registering,    the 
original   double  tube  principle,  invented  by  Negretti  and    Zambra,  specially- 
constructed  for  the  Board  of    Trade  and  Admiralty.      Warranted    to  stand 
a  pressure  of  450  atmospheres.  Price    £2  10    0 

This  manner  of  protecting  the  bulb  was  invented  by  Messrs.  Negretti  and  Zambra  in 
1857,  and  is  described  by  the  late  Admiral  R.  FitzRoy,  in  the  first  number  of  Meteorological 
Papers,  p.  55,  published  July  5th.  1857,  as  follows  : 

"  Referring  to  the  erroneous  readings  of  all  thermometers,  consequent  on  their 
delicate  bulbs  being  compressed  by  the  great  pressure  of  the  ocean,  he  says  : — '  With  a 
view  to  obviate  this  failing  Messrs.  Negretti  and  Zambra  undertook  to  make  a  case  for  the 
weak  bulbs,  which  should  transmit  temperature,  but  resist  pressure.  Accordingly  a  tube 
of  thick  glass  is  sealed  outside  the  delicate  bulb,  between  which  and  the  casing  is  a  space 
all  round,  which  is  nearly  filled  with  mercury.  The  small  space  not  so  filled  is  a  vacuum, 
into  which  the  mercury  can  be  expanded,  or  forced  by  heat  or  mechanical  compression, 
without  doing  injury  to  or  even  compressing  the  inner  or  much  more  delicate  bulb.'" 

The  bulb  of  the  Thermometer  thus  protected  resists  the  pressure  of  the  ocean,  which 
varies  according  to  its  depth — that  of  three  thousand  fathoms  being  something  like  three 
tons  pressure  upon  the  square  inch. 

79.  Negretti     and     Zambra's     Small      Deep       Sea      Sounding 
Thermometers,     the     so-called     Dr.     Miller's    pattern    in     Copper.    Case. 

Price     £2  10    0        £330 

R.  H.  SCOTT,  Esq.,  F.R.S.,  in  a  paper  published  in  the  Journal  of  the  Meteo- 
rological Society,  January  17th,  1872,  speaking  of  Negretti  and  Zambra's  Deep- 
Sea  Thermometers,  described  by  Admiral  FitzRoy  in  the  first  number  of 
Meteorological  Papers,  published  July  5th,  1857,  says  : — 

"  The  number  of  the  thermometers  of  this  particular  pattern,  which  was  supplied  to  the 
Meteorological  Department  of  the  Board  of  Trade  by  Messrs.  Negretti  and  Zambra,  the 
makers,  was  upwards  of  fifty,  and  they  were  supplied  to  several  ships  in  the  Royal  Navy, 
especially  those  employed  on  certain  well-known  deep-sea  sounding  expeditions.  I  was  not 
able  to  find  any  record  of  any  of  these  thermometers  having  been  tested  in  an  hydraulic 
press,  and,  accordingly,  as  soon  as  the  Miller  pattern  thermometer  had  been  definitely 
adopted  by  the  Hydrographer,  it  was  resolved  to  subject  one  of  the  old  thermometers 
(Negretti  and  Zambra's)  in  the  Meteorological  Office  to  the  same  test  as  that  which  the  new 
instruments  were  made  to  undergo,  in  order  to  see  whether  or  not  the  construction  of  the 
original  instruments  offered  sufficient  security  against  alteration  of  the  shape  of  the  bulb, 
owing  to  pressure.  The  experiments  were  carried  out  on  the  28th  of  September,  1869,  in 

45,   COBNHILL,   B.C.,   AND    122,   EEGENT   STREET,   W.,   LONDON.  61 

the  presence  of  Capt.  Toynbee  and  Mr.  Strachan,  and  the  results  of  the  testing  have  been 
published  in  the  report  of  the  Meteorological  Committee  of  the  Royal  Society  for  1869. 
The  concluding  sentence  of  this  report  was  as  follows  (page  32)  : — 

"'The  foregoing  experiments  are  sufficient  to  show  that  the  original  thermometers 
described  by  Admiral  FitzRoy  were  good  and  trustworthy  instruments,  in  so  far  as  regards 
their  capability  of  resisting  pressure.' " 


80.  These  Instruments  differ  from  all  other  Recording  Thermometers  in  the 
following  important  particulars  :— I.  The  Thermometer  contains  pure  mercury 
only,  without  any  alcohol  or  other  fluid.  II.  It  has  no  indices  or  springs,  and 
its  indications  are  by  the  column  of  mercury  only.  III.  It  can  be  carried 
in  any  position,  and  cannot  be  put  out  of  order  except  by  breakage. 
And  chiefly,  it  will  indicate  and  record  the  exact  temperature  at  any  depth  of 
the  sea,  irrespective  of  either  warm  or  cold  currents  or  stratum  through  which 
the  Thermometer  may  have  passed  in  its  descent  or  ascent.  This  last  very 
special  quality  renders  N.  and  Z.'s  Thermometers  superior  for  Deep  Sea  tempera- 
ture to  any  others  ;  for  those  used  in  the  Challenger  expedition  are  liable  to 
give  erroneous  indications,  owing  to  their  indices  slipping,  and  otherwise  getting 
defective  (this  was  proved  by  Messrs.  Negretti  and  Zambra  at  a  Meeting  of  the 
British  Meteorological  Society)  ;  and  under  certain  conditions  of  temperature  it 
is  not  possible  by  these  old  Thermometers  to  obtain  true  temperatures  at  certain 
depths  which  might  be  required. 

The  construction  of  Negretti  and  Zambra's  original  Deep  Sea  Thermometer 
is  as  follows  : — 

In  shape  it  is  like  a  syphon  with  parallel  legs,  having  a  continuous 
communication,  as  seen  in  the  annexed  figure,  69.  The  mounting  of  the 
Thermometer  is  pivoted  on  a  centre,  and  being  attached  in  a  perpendicular 
position  to  a  simple  apparatus  (which  will  be  presently  described),  is  lowered 
to  any  depth  in  the  water  that  may  be  desired.  In  its  descent  the  Thermometer 
acts  as  an  ordinary  instrument,  the  mercury  rising  or  falling  according  to  the 
temperature  of  the  stratum  through  which  it  passes ;  but  so  soon  as  the 
descent  ceases,  and  a  reverse  motion  is  given  to  the  line,  so  as  to  pull  up 
the  apparatus  towards  the  surface,  the  Thermometer  turns  once  on  its 
centre,  first  bulb  uppermost,  and  afterwards  bulb  downwards.  This  causes  the 
mercury,  which  was  in  the  left-hand  column,  first  to  pass  into  the  dilated  syphon 
bend  at  the  top,  and  thence  into  the  right  hand  tube,  where  it  remains, 
indicating  on  a  graduated  scale  the  exact  temperature  at  the  time  it  was 



turned    over.   Fig.  69   shows    the 

position   of   the  mercury  after  the 

instrument  has  been  thus  turned  on 

its  centre.     A  is  the  bulb ;  B  the 

outer  coating  or  protecting  cylinder ; 

C  is  the' space  of  rarefied  air,  which 

is    reduced    if  the    outer   casing  be 

compressed  ;  D  is  a  s  mall  glass  plug 

on    the   principle   of  Negretti   and 

Zambra's  Patent  Maximum  Ther- 
mometer,   which    cuts   off,    in    the 

moment  of  turning,  the  mercury  in 

the   tube    from   that   of  the   bulb, 

thereby  insuring  that  none  but  the 

mercury  in  the  tube  can  be  trans- 
ferred into  the  indicating  column  ; 

E  is  an  enlargement  made  in  the 

bend  so  as  to  enable  the  mercury 

to   pass  quickly  from  one  tube  to 

another  in  revolving  ;  and  F  is  the 

indicating    tube    or   Thermometer 

proper.     In  its  action,  as  soon  as  the 

Thermometer  is  put  in  motion,  and 

immediately  the  tube  has  acquired 

a    slightly    oblique     position,    the 

mercury  breaks  off  at  the  point  D, 

runs  into  the  curved  and  enlarged 

portion  E,  and  eventually  falls  into  the  tube  F,  when  this 

tube  resumes  its  original  perpendicular  position. 

The    contrivance    for   turning    the    Thermometer    over 

may  be  described   as  a   metal  frame  with  a  vertical   screw 

propeller;  to  this  frame  (fig.  70)  the  instrument  is  attached- 

In  its   descent  through  the  water  the  screw  is  lifted  out  of 

gear  and   revolves   freely  on  its  axis  ;  but   so  soon  as   the 

apparatus  is  pulled  up  towards  the  surface  the  screw  falls 

into  gear  and  revolves  in  the  contrary  direction,  turning 
the  Thermometer  over  once,  and  then  becoming  locked  and  immovable, 
the  temperature  is  recorded  for  that  moment.  Price  £10  10  0 

This  arrangement  of  Deep  Sea  Thermometer  (fig.  70)  having  been  found  defective,  Negretti 
and  Zanibra  have  abandoned  its  manufacture — it  being  norc  quite  superseded  by  their  recently 
improved  Thermometers,  particulars  of  which  »vill  be  found  in  the  following  pages.  Our 
description  is  therefore  only  inserted  as  a  matter  of  history  in  connection  with  the 
invention  of  Deep  Sea  Recording  Instruments. 

FIG.  69. 

45,    COENHILL,    E.G.,    AND    122,    KEGENT    STREET,    W.,    LONDON.  63 




81.  "  The  most'successful  Deep- Sea  Thermometer  hitherto  has  been  Six's  Thermometer, 
with  the  bulb  protected  from  pressure,  as  invented  by  NEGRETTI  AND  ZAMBRA  in  1867. 
Nevertheless  there  are  several  disadvantages  inherent  in  the  principle  of  construction  of  Six's 
instrument.  The  indices  are  unreliable,  as,  however  carefully  fitted,  they  may  slip  down  by 
gravity,  and  even  shift  upward  by  sudden  lifting  motion ;  so  that  the  observations  are 
always  more  or  less  liable  to  error  :  the  index  error  also  is  very  liable  to  alter  by  the  shifting 
of  the  spirit,  or  by  bubbles  of  spirit  getting  among  the  mercury ;  and  unless  the  observer  is 
well-trained  in  its  management,  and  takes  care  to  compare  it  with  a  correct  ordinary  ther- 
mometer every  time  it  is  used,  there  is  no  guaranteeing1  its  accuracy  of  indication.  Further, 
its  accuracy  in  its  best  condition  does  not  attain  to  fractions  of  a  degree,  as  it  cannot  be 
read  off  closer  than  about  half  a  degree.  Then  it  must  be  kept  in  the  vertical  position,  or 
it  is  certain  to  become  more  or  less  deranged  in  transit. 

"  However,  so  long  as  it  sufficed  to  observe  the  nearest  degree  of  temperature,  the 
improved  protected  Six's  answers  the  purpose  of  a  deep-sea  thermometer,  with  careful 
management  and  checking  ;  but  lately  the  bottom  temperature  of  shallow  seas  and  of  rivers 
has  come  under  investigation,  and  for  this  purpose  Six's  instrument  is  unsuitable. 

"  Between  the  temperature  of  the  surface  of  the  sea  and  that  at  the  depth  of  a  few 
fathoms,  the  differences  to  be  determined  are  found  to  be  not  degrees  of  the  thermometer, 
but  fractions  of  a  degree  ;  hence,  the  observations  to  be  worth  anything  at  all,  must  be  made 
with  an  undoubtedly  accurate  thermometer. 

"  During  the  last  two  or  three  years  systematic  observations  of  the  surface  and  bottom 
temperatures  have  been  taken  from  the  various  lightships  off  the  British  coasts,  under  the 
direction  of  the  Meteorological  Office.  This  investigation  of  the  temperatures  of  the  British 
seas  has  been  urged  upon  the  Government  by  naturalists  and  physicists  interested  in  the 
question  of  the  food  supply  of  the  people  as  affected  by  the  take  of  fish.  What  is  required 
to  be  made  evident  is,  whether  any,  and  what,  effect  temperature  has  upon  the  habits  and 
migrations  of  fish,  so  as  to  tend  to  a  right  understanding  of  the  conditions  favourable  for 
the  development  of  the  various  species  of  fish,  and  the  best  seasons  and  temperature  indi- 
cations for  their  capture.  This  investigation,  commenced  with  Six's  Thermometers,  has  at 
present  only  shown  that  such  instruments  are  not  sufficiently  reliable  for  the  purpose  ;  and 
it  was  represented  by  the  Government  to  Messrs  NEGRETTI  AND  ZAMBRA,  that  a  more 
perfect  and  stable  deep-sea  thermometer  was  a  desideratum.  They  accordingly  turned  their 
attention  to  the  matter,  and  the  result  is  the  new  STANDARD  DEEP-SEA  THERMOMETER. 

"  The  construction  of  this  thermometer  will  be  readily  understood  by  reference  to  the 
sketch  diagram  fig.  71.  The  bulb  is  cylindrical,  and  mercury  is  the  thermometrical  fluid. 
The  neck  of  the  bulb  is  contracted  in  a  peculiar  manner  at  A,  and  upon  the  shape  and  fine- 
ness of  this  contraction  the  success  of  the  instrument  mainly  depends.  Beyond  A  the  tube 
is  bent,  and  a  small  catch  reservoir  is  formed  at  B,  for  a  purpose  to  be  present/I^  explained. 
At  the  end  of  the  tube  a  small  receptacle,  C,  is  provided.  When  the  tube  is  downward,  the 
glass  contains  sufficient  mercury  to  fill  the  bulb,  tube,  and  a  part  of  the  reservoir  C,  if  the 
temperature  is  high,  leaving  sufficient  space  in  C  for  the  expansion  of  the  mercury.  In  this 
position  no  scale  would  be  possible,  as  the  apparent  movement  of  the  mercury  would  be 
confined  to  the  space  C.  When  the  thermometer  is  held  bulb  upward,  the  mercury  breaks 
off  at  A,  but  by  its  own  weight  flows  down  the  tube,  filling  C  and  a  portion  of  the  tube  above 
C,  in  relation  to  the  resisting  temperature.  The  scale  accordingly  is  made  to  read  upwards 
from  C.  To  set  the  instrument  for  observation  it  is  only  necessary  to  place  it  bulb  down- 

*  Description  condensed  from  "  ENGINEERING,"  Mai-ch  22iid,  1878. 



FIG.  72. 

FIG.  71. 

FIG.  73. 

ward,  then  the  mercury  takes  the  temperature  just  as  an  ordinary  thermometer.  When  at 
any  time  or  at  any  place  the  temperature  is  required,  all  that  has  to  be  done  is  to  turn  the 
thermometer  bulb  upward,  and  keep  it  in  this  position  until  read  off. 

"  The  reading  may  be  taken  at  any  time  after,  for  the  quantity  of  mercury  in  the  lower 
part  of  the  stem  which  gives  the  reading  is  too  small  to  be  sensibly  influenced  by  a  change 
of  temperature,  unless  it  is  very  great,  while  that  in  the  bulb  will  continue  to  contract  with 
greater  cold  and  to  expand  with  greater  heat,  and  in  the  latter  case  some  mercury  will  pass 
the  contraction  A,  and  may  fall  down  and  lodge  at  B,  but  it  cannot  go  further  so  long  as  the 
bulb  is  upward,  and  thus  the  temperature  to  be  read  off  will  not  be  vitiated.  Now,  when- 
ever the  thermometer  can  be  handled,  it  can  readily  be  turned  bulb  upward  for  reading  off 
the  existing  temperature.  At  a  depth  in  the  sea,  some  contrivances  must  be  provided  for 
turning  the  thermometer  bulb  upward.  For  this  purpose  the  thermometer  is  fitted  into 
a  hollow  wooden  frame,  loaded  with  shot,  free  to  move  from  end  to  end  of  it,  and  sufficient 
to  render  the  whole  instrument  just  vertically  buoyant  in  sea-water. 

"  In  using  the  thermometer  a  cord  is  rove  through  the  hole  in  the  frame  nearest  the 
bulb,  and  the  instrument  is  fastened  by  this  cord  to  the  sounding  line.  In  descending  the 
thermometer  will  be  pulled  down  with  the  bulb  downwards  ;  but  upon  being  pulled  up,  the 
instrument,  owing  to  the  resistance  through  the  water,  and  consequent  displacement  of  its 
centre  of  gravity,  will  turn  over  and  come  up  bulb  uppermost,  the  temperature  of  the  spot 
where  it  turned  over  will  then  be  indicated,  as  shown  in  the  illustrations.  See  figures 
72  and  73. 

"  As  regards  the  thermometer  itself  it  was  necessary,  in  order  to  make  it  perfectly 
satisfactory,  to  protect  it  against  pressure,  even  if  intended  for  shallow  seas,  as  well  as  for 

45,   CORNHILL,   E.G.,   AND   122,    REGENT   STREET,    W.,   LOKDON.  65 

the  deepest.  For  whether  used  in  deep  or  shallow  water,  unless  withdrawn  from  pressure, 
its  indications  would  always  be  more  or  less  in  error.  Like  an  ordinary  thermometer  it  is 
devoid  of  air,  and  so  quite  different  from  Six's,  which,  containing  compressed  air,  has  a 
certain  internal  resistance.  Hence  it  would  be  more  affected  by  pressure  than  Six's,  how- 
ever thick  the  glass  of  the  bulb.  By  the  simple  expedient  of  placing  the  thermometer 
entirely  in  a  shield  of  glass  hermetically  sealed  (see  fig.  4  on  next  page),  the  effect  of  external 
pressure  is  entirely  eliminated.  The  shield  must  of  course  be  strong,  but  need  not  be 
exhausted  of  air.  It  must,  however,  render  the  enclosed  thermometer  more  difficult  to  be 
affected  by  changes  of  temperature  ;  in  other  words,  it  will  make  it  sluggish. 

"  To  counteract  this  sluggishness,  in  that  portion  of  the  shield  surrounding  the  bulb, 
some  mercury  is  introduced,  and  confined  there  by  a  partition  cemented  in  the  shield  around 
the  neck  of  the  thermometer  bulb.  This  mercury  acts  as  a  carrier  of  heat  from  the  exterior 
of  the  shield  to  the  interior  of  the  thermometer  :  and  the  efficacy  of  this  arrangement  has 
been  experimentally  determined,  the  instrument  thus  protected  being,  in  fact,  far  superior 
in  sensibility  to  Six's  thermometer. 

"  So  long  as  the  shield  withstands  the  pressure,  that  is,  does  not  break,  the  thermometer 
will  be  unaffected  by  pressure,  and  there  is  abundant  experience  to  show  that  such  a  shield 
will  stand  the  pressure  of  the  deepest  ocean.  The  greatest  pressure  can  never  affect  a 
thermometer  so  protected.  Doubtless  the  shield  will  be  compressed  a  little  under  great 
pressure,  but  this  can  never  exert  an  internal  pressure  sufficient  to  have  an  appreciable 
effect  upon  the  thermometer.  This  method  of  shielding  is  quite  efficacious,  and  deep-sea 
thermometers  so  protected  do  not  require  to  be  tested  for  pressure  in  the  hydraulic  press. 
The  thermometer  will  simply  require  to  be  tested  for  sensitiveness  and  for  errors  of  gradu- 
ation very  accurately  ;  because  it  is  a  standard  instrument  adapted  to  determine  very  small 
differences  of  temperature  as  well  as  large  ones,  even  one  or  two- tenths  of  a  degree  in 
shallow  waters.  The  test  for  sensitiveness  should  determine  how  many  seconds  the  instru- 
ment requires  to  take  up  a  change  of  5  deg.  rise  or  fall  ;  and  the  time  has  been  found  from 
5  to  10  seconds. 

"  A  considerable  number  of  these  instruments  have  already  been  tested  at  the  Kew 
Observatory  with  perfectly  satisfactory  results,  which  place  beyond  doubt  their  value  as 
Standard  Deep-sea  Thermometers. 

"  This  instrument  possesses  great  advantages.  It  has  no  attached  scale,  th'e  figuring 
and  graduations  are  distinctly  marked  on  the  stem  itself,  and  the  shield  effectually 
preserves  them  from  obliteration  by  sea-water.  The  part  of  the  stem  which  forms  the 
background  to  the  graduations  is  enamelled  white,*  to  give  distinctness  to  the  mercury. 

"  The  hole  at  the  top  of  the  frame  is  for  the  purpose  of  lowering  and  keeping  the 
thermometer  upright  until  it  has  reached  the  water.  This  is  effected  by  putting  a  cord 
through  the  hole,  and  both  ends  of  it  kept  in  the  hand  until  the  thermometer  has  reached  the 
water,  then  one  end  is  let  go  and  the  cord  pulled  on  board  ;  this  operation  is  not  imperative, 
but  it  saves  the  thermometer  from  being  knocked  about  previous  to  reaching  the  water." 
Negretti  and  Zambia's  Patent  Standard  Marine  Thermometer  (fig.  72)  .  Price  £2  10  0 

*  Enamelling  the  bac/c  of  Thermometer  Tubes  is  on  important  invention  by  Negretti  and  Zambra.  Most  of  the 
extremely  sensitive  Thermometers  that  are  now  made  (such  as  Clinical  Thermometers)  would  have  been  almost 
useless  but  for  this  improvement. 

1  cubic  foot  of  Sea  Water  weighs  62*425  lbs.=557  cwt ,  or  0-028  of  a  ton. 

Sea  Water  freezes  at  28°.     Boils  at  213  2  ;  variable  with  the  density. 

80  miles  from  the  Island  of  St.  Thomas,  at  a  depth  of  3  875  fathoms,  the  temperature  of 
the  Sea  was  found  to  be  34£°  Fahrenheit ;  the  pressure  at  this  depth  4*  tons  to  square  inch. 

The  pressure  at  100  feet  is  found  by  Divers  difficult  to  bear  for  any  lengthened  period. 
Man  cannot  sustain  a  greater  pressure  than  6  Fathoms,  or  120  feet.  Weights  of  6  or  8 
hundredweight  require  two  Hours  to  fall  through  3  miles  of  Sea  Water,  owing  to  the 
friction  of  the  water  on  the  rope  or  wire. — Dr.  CARPENTER. 




H     c 

FIG.  l. 

FIG.  3. 

FIG  4. 

FIG.  2. 

82.  NEGRETTI  &  ZAMBRA'S  Improved  Standard  Deep-sea  Thermometer  has  been  abundantly 
proved  to  be  the  only  thermometer  that  ought  to  be  used  in  researches  into  the  temperature 
of  the  sea  below  the  surface.  It  is  quite  applicable  for  testing  the  temperature  of  the  sur- 
face water,  but  merely  for  this  purpose  a  less  expensive  instrument  would  usually  be 
employed.  For  taking  temperatures  at  moderate  depths,  from  a  few  feet  to  a  few  hundred 
fathoms,  NEGRETTI  AND  ZAMBRA'S  Wooden  Float  form  amply  suffices  and  is  quite  suitable. 
The  only  objection  that  has  been  raised  to  this  wooden  float  is,  that  in  sounding  to  great 
depths  a  check  upon  the  line,  caused  by  the  motion  of  the  ship  due  to  the  heave  of  the  sea, 
may  make  it  turn  over  and  register,  so  that  the  temperature  at  the  desired  depth  is  not 
obtained.  In  very  deep  soundings  it  is  often  desirable  to  have  a  series  of  thermometers 

45,    COBNHILL,    E.G.,   AND    122,    REGENT   STREET,   W.,    LONDON.  67 

upon  the  line  at  different  depths ;  and  in  this  case  the  frequent  checks  and  stoppages 
upon  the  line  during  the  hauling  up,  either  from  the  pitching  of  the  ship  or  in  detaching  the 
thermometers  as  they  arrive  at  the  surface,  lead  to  some  uncertainty  in  the  results.  To  do 
away  with  all  doubt  as  to  the  accuracy  of  the  record  brought  up  by  each  thermometer  is  the 
object  of  the  new  form  of  the  Standard  Deep-sea  Thermometer.  The  improvement  is  due  to 
suggestions  kindly  furnished  to  NEGBETTI  AND  ZAMBBA  by  Commander  MAGNAGHI,  of  the 
Royal  Italian  Navy.  By  means  of  it  the  thermometer  may  be  attached  to  any  part  of  the 
line  during  the  descent ;  and  after  the  first  regular  haul  in  of  from  10  to  80  feet,  according 
to  adjustment,  any  number  of  stoppages  or  any  amount  of  line  may  be  afterwards  run  out 
without  altering  the  temperature  obtained  at  the  commencement  of  hauling  up.  Several 
thermometers  can  now  be  fastened  upon  the  line  and  serial  temperatures  obtained  at  any 
required  depth  with  certainty. 

The  apparatus  will  be  best  understood  by  reference  to  the  accompanying  figures 
(Nos.  1  and  2).  A  is  a  metallic  frame  in  which  the  case  B,  containing  the  thermometer, 
is  pivoted  upon  an  axis  H,  but  not  balanced  upon  it.  C  is  a  screw-fan  attached  to  a 
spindle,  one  end  of  which  works  in  a  socket  D,  and  on  the  other  end  is  formed  the 
thread  of  a  screw  E,  about  half  an  inch  long,  and  just  above  it  is  a  small  pin  or  stop  P  on 
the  spindle.  G  is  a  sliding  stop-piece  against  which  the  pin  F  impinges  when  the  thermo- 
meter is  adjusted  for  use.  The  screw  E  works  into  the  end  of  the  case  B  the  length  of  play 
to  which  it  is  adjusted.  The  number  of  turns  of  the  screw  into  the  case  is  regulated  by 
means  of  the  pin  and  stop-piece.  The  thermometer  in  its  case  is  held  in  position  by  the 
screw  E,  and  descends  into  the  sea  in  this  position  (Fig.  1),  the  fan  C  not  acting  during  the 
descent  because  it  is  checked  by  the  stop  F.  When  ascent  commences  the  fan  revolves, 
raises  the  screw  E,  and  releases  the  thermometer,  which  then  turns  over  and  registers  the 
temperature  at  that  spot,  owing  to  the  axis  H  being  below  the  centre  of  gravity  of  the  case 
B  as  adjusted  for  the  descent.  Each  revolution  of  the  fan  represents  about  10  feet  of  move  - 
ment  through  the  water  upwards,  so  that  the  whole  play  of  the  screw  requires  70  or  80  feet 
ascent  ;  therefore  the  space  through  which  the  thermometer  should  pass  before  turning  over 
must  be  regulated  at  starting.  If  the  instrument  ascends  a  few  feet  by  reason  of  a  stoppage 
of  the  line  while  attaching  other  thermometers,  or  through  the  heave  of  the  sea,  or  any 
cause  whatever,  the  subsequent  descent  will  cause  the  fan  to  carry  back  the  stop  to  its  initial 
position,  and  such  stoppages  may  occur  any  number  of  times  provided  the  line  is  not  made 
to  ascend  through  the  space  necessary  to  cause  the  fan  to  release  the  thermometer.  When 
the  hauling-in  has  caused  the  turnover  of  the  thermometer  the  lateral  spring  K  forces  the 
pin  L  into  a  slot  in  the  case  B  and  clamps  it  (as  seen  in  fig.  2)  until  it  is  received  on  board 
so  that  no  change  of  position  can  occur  in  the  rest  of  the  ascent  from  any  cause.  The  case 
B  is  cut  open  to  expose  the  scale  of  the  thermometer,  and  is  also  perforated  to  allow  the  free 
entry  of  the  water. 

The  construction  of  the  Thermometer  will  be  understood  by  referring  to  Figs.  3  and  4 
and  also  to  the  description  given  on  page  63  (fig.  71) 

Price  for  NEGEETTI  AND  ZAMBEA'S  New  Patent  Improved  Frame  Standard  Deep-Sea 
Thermometer,  as  fig.  1. 

The  Hydrographic  Bureau  at  Washington  published  lately  the  following  results  of  a 
series  of  observations  carried  out  in  order  to  determine  the  length,  depth,  and  duration  of 
ocean  waves  : — 

The  longest  wave  hitherto  observed  is  said  to  have  had  a  length  of  half-a-mile,  and  to 
have  spent  itself  in  23  seconds.  During  storms  in  the  North  Atlantic  waves  sometimes 
extend  to  a  length  of  500  ft.  and  600  ft.,  and  last  from  10  to  11  seconds. 

The  most  careful  measurements  of  the  height  of  waves  give  from  44  to  48  feet  as  an 
extreme  limit ;  the  average  height  of  great  waves  is  about  30  ft. 

These  measurements  refer  to  ordinary  marine  action,  and  do  not  relate  to  earthquake 
action  or  other  exceptional  agencies. 

F  2 



THE  instruments  used  for  observing  the  amount  of  moisture  contained  in 
the  atmosphere  are  called  Hygrometers.  They  are  without  doubt  of  all 
Meteorological  instruments  the  most  useful  and  valuable. 

To  ascertain  with  exactness  the  Hygrometric  condition  of  the  air  is  of  the 
utmost  importance  both  to  the  Physician  and  Agriculturist.  By  observing  the 
varying  amount  of  vapour  or  moisture  in  the  air,  the  one  is  enabled  to  regulate 
its  condition  as  best  suited  to  his  patient's  requirements,  and  the  other  by  closely 
watching  the  movements  of  the  Barometer  in  connection  with  the  Hygrometer 
can  anticipate  probable  atmospheric  changes  that  may  prove  beneficial  or 
injurious  to  his  crops. 

There  are  many  Hygrometers  constructed  as  Weather  Indicators  only, 
simply  showing  the  approximate  condition  of  the  air  if  it  be  wet  or  dry.  Such 
instruments,  however  ingenious,  are  not  of  any  scientific  value.  For  more  exact 
and  precise  observation  the  Hygrometers  of  Daniell,  Regnault,  and  Mason  are 
chiefly  used — the  latter,  viz.,  Mason's,  from  its  extreme  simplicity  is  now 
universally  in  use,  and  in  connection  with  the  valuable  tables  compiled  by 
James  Grlaisher,  Esq.,  F.B.S.,  the  dew  point  can  be  ascertained  with  great 
exactness  and  ease. 

In  connection  with  the  Hygrometer,  the  dew  point  will  be  frequently 
spoken  of.  This  may  be  described  in  a  few  words  as  the  amount  of  water 
which  the  air  can  sustain  in  an  invisible  form  increasing  with  the  temperature  ; 
but  for  every  definite  temperature  there  is  a  limit  to  the  amount  of  vapour 
which  can  be  thus  diffused.  When  the  air  is  cooled  the  vapour  present  may  be 
more  than  it  can  sustain ;  part  will  then  be  condensed  either  in  the  form  of 
dew,  rain,  hail,  or  snow.  The  temperature  which  the  air  has  when  it  is  so  fully 
saturated  with  vapour  that  any  excess  will  be  deposited  as  dew,  is  called  the 

"  To  measure  the  quantity  of  dew  deposited  each  night,  an  instrument  is 
used  called  a  Drosometer.  The  most  simple  process  consists  in  exposing  to  the 
open  air  bodies  whose  exact  weight  is  known,  and  then  weighing  them  carefully 
when  covered  with  dew.  According  to  Wells,  locks  of  wool,  weighing  about 
eight  grains,  are  preferred,  divided  into  spherical  masses  of  the  diameter  of 
about  two  inches.'' — Kcemtz. 

45,    COBNHILL,    E.G.,   AND    122,    BEGENT    STEEET,    W.,    LONDON.  69 

83.  Saussure's  Hygrometer  (fig.  74),  for  showing  changes 
in  the  hygrometric  condition  of  the  atmosphere  on  a  graduated 
arc,  by  the  contraction  and  elongation  of  a  human  hair,  this  acting 
the  reverse  of  string  or  cord,  stretching  when  moist  and  contract- 
ing when  dry.     A  thermometer  is  attached  to  the  scale. 

Price,     £1  10    0 

Although  a  most  elaborate  Treatise  on  the  construction  and 
use  of  this  Hygrometer  was  written  by  its  inventor,  M.  Horace 
Benedict  de  Saussure,  Professor  of  Philosophy,  at  Geneva,  in  1783, 
this  instrument  may  be  regarded  more  as  an  ornamental  curiosity 
than  of  any  scientific  value.  FIG  74. 

84.  Leslie's   Thermometric  Hygrometer  (fig  75).     It  will  be  seen 
that  Leslie's  instrument  is  the  elementary  form  of  Mason's  Wet  and  Dry  Bulb 
Hygrometer,  by  which  it  is  entirely  superseded. 

This  instrument  consists  of  a  glass  tube,  terminated  with  a  bulb  at  each 
end,  as  fig.  75.  The  tube  is  partly  filled  with  sulphuric  acid,  tinged  by  carmine. 
One  of  the  balls  is  covered  with  muslin,  and  kept  continually  moistened  with 
water,  drawn  from  a  vase  placed  near  it  by  the  capillary  attraction  of  a  few 
strands  of  cotton- wick.  The  descent  of  the  coloured  liquid  in  the  other  stem 
will  mark  the  diminution  of  temperature  caused  by  the  evaporation  of  the  water 
from  the  humid  surface.  The  drier  the  ambient  air  is,  the  more  rapidly  will 
the  evaporation  go  on ;  and  the  cold  produced  will  be  greater.  When  the  air 
is  nearly  saturated  with  moisture,  the  evaporation  goes  on  slowly  ;  the  cold 
produced  is  moderate,  because  the  ball  regains  a  large  portion  of  its  lost  heat 
from  surrounding  bodies.  The  degree  of  refrigeration  of  the  ball  is  an  index  of 
the  dryness  of  the  air. 

When  this  hygrometer  stands  at  15°,  the  air  feels  damp ;  from  30°  to  40°, 
we  reckon  it  dry ;  from  50°  to  60°,  very  dry ;  and  from  70°  upwards,  we  should 
call  it  intensely  dry.  A  room  would  feel  uncomfortable,  and  would  probably 
be  unwholesome,  if  the  instrument  in  it  did  not  reach  30°.  In  thick  fogs  it 
keeps  almost  at  the  beginning  of  the  scale.  Price,  £110 

85.  Daniell's    Hygrometer,  for  ascertaining   the  dew-point  by  direct 
observation  (fig.  76),  invented  about  the  year  1820,  by  the  late  Professor  Daniell, 
of  King's  College,  London. 

It  consists  of  a  glass  tube,  bent  twice  at  right  angles,  and  terminating,  at 
each  end,  in  a  bulb.  In  the  long  limb  of  the  tube  is  enclosed  a  delicate 
thermometer,  which  descends  to  the  centre  of  the  bulb,  which  is  about  three- 
parts  filled  with  sulphuric  aether.  All  the  other  parts  of  the  tube  are  carefully 
freed  from  air,  so  that  they  are  occupied  by  the  vapour  of  the  aether.  This  bulb 
is  made  of  black  glass  ;  the  other  bulb  on  the  shorter  limb  is  transparent,  and 



FIG.  75.  FIG.  76.  FIG.  77. 

covered  with  a  piece  of  fine  muslin.     The  support  for  the  tube  has  a  delicate 
thermometer  attached,  to  show  the  temperature  of  the  external  air. 

This  instrument  gives  the  dew-point  by  direct  observation,  and  is  to  be 
used  at  an  open  window  facing  the  north  in  the  following  manner  : — Having 
fixed  the  tube  upon  the  stand,  with  the  bulbs  vertically  downward,  the  ^Ether 
is  all  caused  to  flow  into  the  lower  ball  by  inclining  the  tube.  The  temperature 
of  the  air  is  noted  by  the  exposed  thermometer.  Then  some  ^Efcher  is  poured 
upon  the  muslin-covered  bulb.  The  rapid  evaporation  of  this  ^Ether  cools  the 
bulb  and  causes  condensation  of  the  ^Ethereal  vapour  in  its  interior.  This  gives 
rise  to  rapid  evaporation  of  the  Mtlaer  in  the  lower  bulb,  whereby  its  temperature 
is  greatly  reduced.  The  air  in  the  vicinity  is  deprived  of  its  warmth  by  the 
cold  bulb,  and  is  soon  cooled  to  the  temperature  at  which  it  is  perfectly  saturated 
with  the  vapour  which  it  contains.  Cooled  ever  so  little  below  this  temperature, 
some  aqueous  vapour  will  be  condensed,  and  will  form  a  dew  upon  the  black- 
glass  bulb.  At  the  first  indication  of  the  deposit  of  dew  the  reading  of  the 
internal  thermometer  is  taken  :  which  is  the  dew-point.  In  very  damp  or  windy 
weather  the  .^Ether  should  be  slowly  dropped  on  the  bulb,  otherwise  the  descent 
of  the  mercury  in  the  Thermometer  is  so  rapid  as  to  render  it  difficult  to  be 
certain  of  the  temperature.  Should  this  occur,  the  observation  may  be  repeated 
by  watching  the  temperature  at  which  the  ring  of  dew  disappears,  the  mean  of 
the  two  readings  will  be  the  correct  point  of  precipitation.  The  greatest  differ- 
ence observed  by  Mr.  Daniell  in  the  course  of  four  months'  daily  experiments 
between  the  external  thermometer  and  the  internal  one  at  the  moment  of 

45,    COKNHILL,    E.G.,   AND    122,    EEGENT    BTRKET,    WM    LONDON.  71 

precipitation  in  the  natural  state  of  the  atmosphere  was  twenty  degrees.  When 
Darnell's  Hygrometer  is  required  to  act  merely  as  a  weather-glass,  to  predict 
the  greater  or  less  probability  of  rain,  &c.,  the  difference  between  the  con. 
stituent  temperature  of  the  vapour  (shown  by  the  interior  thermometer),  and 
the  temperature  of  the  air  (shown  by  the  exterior  thermometer),  is  all  that  is 
necessary  to  be  known.  The  probability  of  rain  or  other  precipitation  of 
moisture  from  the  atmosphere,  is  in  inverse  proportion  to  this  difference.  There 
are  several  difficulties  connected  with  the  use  of  Daniell's  Hygrometer  that  are 
in  a  great  measure  overcome  in  Regnault's  Instrument.  Fig.  76  Price,  £330 

86.  Jones's  Hygrometer   (fig.  77).     This  instrument  is   the  same  in 
principle  as  Daniell's  Hygrometer,  but  simpler  in  its  construction.     The  tube 
of  the  Mercurial  Thermometer  is  bent  so  as  to  bring  its  bulb  vertical  and 
parallel  with  its  stem.     This  bulb  is  one  inch  long,  and  of  a  conical  shape,  with 
a  flattened  top  or  surface  of  black  glass   projecting  a  little  beyond  the  sides. 
Below  the  flat  surface  this  bulb  is  covered  with  black  silk.     The  Hygrometer 
is  mounted  and  supported  on  a  brass  stand  in  such   a  manner  that  the  black 
surface  can  be  inclined  towards  the  light.     When  used  the  temperature  of  the 
air  is  first  to  be  noted.     ./Ether  is  to  be  poured  on  to  the  silk  cover  of  the  bulb, 
and  the  condensation  of  moisture  takes  place  upon  the  black  surface  of  the 
bulb.     Then,  by  again  noting  the  temperature,  the  dew  point  may  be  known. 

Price,    £2  10    0 

87.  Regnault's  Condenser  Hygrometer,  (fig.  78),  for  ascertaining  by 
direct  observation  the  dew-point,  is  superior  to  Daniell's,  from  its  being  more 
certain  in  its  indications,  and  economical  in  use.     It  consists  of  two  highly- 
polished  silver  cylinders,  into  the  upper  part  of  which  are  cemented  thin  glass 
tubes  ;  these  have  brass  covers,  arranged   to  receive  and   support  two  delicate 
Standard  Thermometers,  the  bulbs  of  which  descend  nearly  to  the  bottom  of 
the  silver  portion  of  these  chambers.     Each  chamber  has  a  small  internal  tube 
carried  down  from  the  brass  cap  to  within  a  short  distance  of  the  bottom,  to 
admit  the  passage  of  the  air,  which  is   drawn  through  both  chambers  by  an 
Aspirator,   (fig.   78*)   connected  to  the  base  of  the  hollow  upright  and  arms 
supporting  the  cylinders. 

To  use  this  Hygrometer,  aether  is  poured  into  one  chamber  sufficient  to  cover 
the  bulb  of  the  thermometer,  and  then  the  thermometers  being  inserted  into 
both  cylinders  the  instrument  is  now  connected  to  the  aspirator,  and  by  it  the 
air  is  drawn  through  both  cylinders  down  the  internal  tubes,  passing  in  one 
chamber  in  bubbles  through  the  aether,  and  in  the  other  chamber  simply  around 
the  thermometer.  The  tube  in  this  empty  cylinder  is  of  such  a  diameter  as  to 
ensure  similar  quantities  of  air  passing  through  each  chamber. 

After  a  short  time  the  passage  of  the  air  through  the  aether  will  cool  it  down 
to  the  dew-point  temperature  and  the  external  portion  of  the  silver  chamber 
containing  the  aether  will  become  covered  with  moisture.  The  degree  shown 



FIG.  78. 

FIG.  79. 

by  the  thermometer  in  the  aether  at  that  instant  will  be  the  temperature  of  the 
dew-point ;  the  second  thermometer  showing  the  temperature  of  the  air  at  the 
time  of  observation. 

Price,  in  case ....      £5    5    0 

Aspirator  for  ditto  (fig.  78*) £1  15     0  to  2  15    0 

88.  Regnault's  Condenser  Hygrometer  (fig.  56),  of  simpler  form, 
only  one  cylinder  or  chamber  being  nsed.  The  air  in  this  arrangement  is  blown 
through  the  aether  by  the  mouth.  A  small  thermometer  is  attached  to  the  stand 
to  show  the  temperature  of  the  external  air. 

Price,  in  Case,  with  ^Ether  Bottle  (fig.  79) £3  10    0 

For  practical  utility  and  convenience  in  use  the  Wet  and  Dry  Bulb  Hygro- 
meter is  vastly  superior  to  all  others.  The  engravings,  N"os.  80  to  86,  will  show  the 
various  forms  of  Negretti  and  Zambra's  Hygrometers  from  the  simplest  to  the 
Standard  instruments  as  manufactured  by  Negretti  and  Zambra  for  the  various 
Scientific  Observatories  and  Societies,  the  Government  Meteorological  Stations, 
the  Metropolitan  and  County  Hospitals,  &c.,  &c.  Most  of  these  Hygrometers 
'  have  Negretti  and  Zambra's  Patent  Porcelain  Scales  and  Enamelled  Tubes. 

89.  Wet  and  Dry  Bulb  Hygrometer,  simple  form,  on  a  stand  (fig.  80) 
for  table  or  shelf.  Price,  12s.  6d.,  16s.,  and  £110 

90.  Ditto  Ditto  Ditto       plain,  portable,  brass  stand 
and  metal  cover  (fig.  81).  Price,    £1  10    0 

45,  CORNHILL,  E.G.,  AND  122,  REGENT  STREET,  W.,  LONDON. 


FIG.  80.  FIG.  82.  FIG.  83. 

91.  Wet    and  Dry    Bulb    Hygrometer  with  Wood  or  Zinc  Scales, 
mounted  in  a  Japanned  Metal  Case,  suited  for  out-door  use,  the  Greenhouse 
or  Conservatory  (fig.  82).  Price,    £0  14    0 

92.  *  Ditto  Ditto  with  Negretti  and  Zambra's  Patent 
Porcelain  Scale,  in  Japanned  Case,  as  fig.  82.  Price,    £110 

93.  Mason's  Hygrometer,  portable  brass-jointed  tripod-stand  and  metal 
cover  (fig.  83).  Price,     £3    3    0 

94.  Negretti     and     Zambra's    Standard    Dry    and    Wet    Bulb 
Hygrometer,    or     Psychrometer     (fig.    84),    consists     of    two     parallel 
Thermometers,  as  nearly  identical  as  possible,  mounted  on  a  wooden  bracket, 
one  marked  dry,  the  other  wet.     The  bulb  of  the  wet  thermometer  is  covered 
with  thin  muslin  and  round  the  neck  of  the  stem  is  twisted  or  tied,  as  seen  in 
fig.  84*,   conducting-threads  of  lamp-wick,  or  common   darning- cotton,  these 
pass  down  into  a  vessel  of  water,  placed  at  such  a  distance  as  to  allow  a  length 
of  conducting-thread  of  about  three  inches  ;  the  cup  or  glass  being  placed  on 
one  side,  and  a  little  beneath,   so  that  the  water  within  may  not  affect  the 
reading  of  the  Dnj  Bulb  Thermometer.     In  observing,  the  eye  should  be  placed 
on  a  level  with  the  top  of  the  mercury  in  the  tube,  and  the  observer  should 
refrain  from  breathing  whilst  taking  an  observation.     The  temperature  of  the 
air  and  of  the  evaporation  is  given  by  the  readings  of  the  two  thermometers,  from 
which  can  be  calculated  the  dew  point,  Tables  being  furnished  for  that  purpose 
with  the  instrument. 

The  dry  bulb  thermometer  indicates  the  temperature  of  the  air  itself ;  while 
the  wet  bulb,  cooled  by  evaporation,  shows  a  lower  temperature  according  to 
the  amount  of  and  rapidity  of  evaporation. 

This  instrument  is  used  by  the  Members  of  the  British  Meteorological 

Society,  and  supplied  to  them  by  Negretti  and  Zambra  (fig.  84)  Price    £220 

Glaisher's  Tables  for  ditto        026 


FIG.  85. 

FIG.  84. 

95.  Wet  and  Dry  Bulb  Hygrometer  for  external  Window  use,  with 
engraved   Opal    Glass   or  Porcelain  Scales,   mounted    on    a   substantial    and 
Ornamental  wood  and  metal  bracket,  fitted  with  a  clamping  screw  for   setting 
the  scale  at  any  convenient  angle  for  observation,  as  fig.  85. 

Price  £2  10     0  and  £330 

96.  Portable  Wet  and  Dry  Bulb  Hygrometer,     (fig.  86.)     A  most 
compact  and  convenient  form  of  Hygrometer,  invented  by  Negretti  and  Zambra, 
as  a  companion   instrument  to  their  Small    Patent  Maximum  and   Minimum 
.Registering  Thermometers  and  Pocket  Aneroid  Barometer  (figs.  26  and  61), 
pages  26  and  51.     The   Hygrometer,    with  stand  and  water  cistern,  is  fitted 
into  a  neat  Pocket  case.  Price       .       .        .        .£220 

Larger  Standard  size        .          2  10    0 

45,    CORNHILL,    E.G.,    AND    122,    REGENT   STREET,    W.,    LONDON. 


FIG.  81.  FIG.  86. 

97.  Dines*  Hygrometer.     We  notice  this  apparatus  chiefly  as  a  matter 
of  record.     It  is  fully  described  along  with  an   account  of  some  remarkable 
results  obtained  from  its  use  by  its  inventor,  George  Dines,  Esq.,  in  the  Journal 
of    the  Meteorological    Society ;    but,  like   Daniell's,    Regnault's,  and  Jones's 
Hygrometers,  it  is  not  self-acting,  and  not  so  simple  in  its  use  as  the  Wet  and 
Dry  Bulb  Instrument.      Therefore,  this  Apparatus  will  only  be  supplied   to 
special  order.  Price,  £2  12    6  to  3    3    0 

98.  Registering  Hygrometer,  constructed  with  Negretti  and  Zambra's 
Patent  Maximum  and  Minimum  Registering  Thermometers,  each  fitted  up  as  a 
wet-bulb   thermometer,    to  record    the    highest   and   lowest    temperature   of 
evaporation  during  any  interval  of  time.  Price,  £330 

99.  Hygrometer  Screen.     The  engraving  (fig.  89),  page  79,  shows  one 
of  the  best  methods  of  fixing  up  and  protecting  the  Hygrometer,  the  louvre 
boarded  case  affording  free  passage  to  the  air  and  at  the  same  time  protection 
from  rain,  suow,  the  sun's  rays,  or  radiated  heat  from  surrounding   bodies. 
This    Screen    should  be  fixed  at  about  four  feet  from  the  ground,   the  door 
facing  due  North.     If  fixed  against  a  wall,  there  should  be  left  a  space  between 
the  back  of  the  Screen  and  the  wall,  at  least  three  or  four  inches,  to  insure  a 
free  circulation  of  air.     It   need  hardly  be  pointed  out  that  the  Screen  must 
be  securely  fastened  to   its  support,   wherever   used,  to  prevent  vibration  or 
injury  from  wind.     This  arrangement  is  specially  recommended  by  the  Board 
of  Trade  for  Marine  Service  both  for  Hygrometers  and  Thermometers. 

Price,  £1     1     0,  or  made  to  Order. 

100.  From  the  readings  of  the  two  thermometers,  the  dew-point   can  be 
deduced  by  formulae  (that  known  as  Apjohn's  is  considered  the  most  theoretically 
true),  or  from  the  valuable  Hygrometric  Tables  by  J.  Glaisher,  Esq.,  F.R.S. 


101.  For  practical  purposes  in  estimating  the  comparative  humidity,  the 
annexed  table,  which  is  a  reduction  from  Mr.  Glaisher's  elaborate  work,  will 
be  sufficient. 

by  the 
Dry  Bulb 

Difference  between  Dry-Bulb  and  Wet-Bulb  Readings. 







Degree  of  Humidity. 













































































































































































The  total  quantity  of  aqueous  vapour  which  at  any  temperature  can  be 
diffused  in  the  air  being  represented  by  100,  the  percentage  of  vapour  actually 
present  will  be  found  in  the  table  opposite  the  temperature  of  the  dry-bulb 
thermometer,  and  under  the  difference  between  the  dry-bulb  and  the  wet-bulb 
temperatures.  The  degree  of  humidity  for  intermediate  temperatures  and 
differences  to  those  given  in  the  table  can  be  easily  estimated  sufficiently 
accurately  for  most  practical  purposes.* 

This  table  will  be  found  serviceable  to  Horticultarists,  since  it  will  enable 
them  to  estimate  the  chilling  effect  of  dew  or  hoar-frost  on  tender  plants. 

In  England  the  usual  difference  between  the  thermometer  readings, — in 
the  open  air,  shaded  from  the  sun,  reflected  heat,  and  currents  of  air, — ranges 
from  one  to  twelve  degrees.  In  hot  and  dry  climates,  as  India  and  Australia, 
the  range  out  of  doors  has  been  found  as  much  as  30°. 

A. still  more  comprehensive  but  simple  Dew-Point  or  Humidity  Table  has  been  recently  published 
by  William  Marriott,  Esq.,  F.M.S.,  price  6d. 

45,  CORNHILL,  E.G.,  AND  122,  REGENT  STREET,  W,,  LONDON.        77 

The  Summer  and  Autumn  of  the  year  1859  were  specially  remarkable  for 
a  most  unusual  Thermometric  and  Hygrometric  condition  of  atmosphere,  and 
Londoners  will  long  remember  the  state  of  the  River  Thames  during  that  period. 
Deficiency  of  water  supply  during  1858  and  1859,  and  great  evaporation 
(often  to  fourteen  degrees  of  thermometrical  difference  in  Mason's  Hygrometer), 
caused  a  condition  of  its  stream  excessively  offensive,  if  not  actually  pestilential 
and  unhealthy.  Everywhere  a  want  of  water  was  felt,  and  this  had  been 
of  considerable  duration.  In  August  the  heat  reached  92°  (in  places  where 
usually  summer  heat  is  not  above  80Q),  and  the  temperature  of  evaporation 
was  78°,  by  the  same  hygrometer. 



102.  The  muslin  on  the  bulb  of  the  Hygrometer  should  be  washed 
occasionally  by  pouring  water  over  the  bulb  ;  and  it  should  be  replaced  by  a 
fresh  piece  at  least  once  a  month.  Accuracy  depends  very  much  upon  keeping 
the  wet  bulb  clean,  free  from  dust,  and  not  too  wet. 

When  the  bulb  is  frozen,  some  cold  water  should  be  taken  from  nnder 
ice,  being  cautious  to  raise  its  temperature  as  little  as  possible,  and  the 
thermometer  bulb  should  be  wetted  with  it  by  means  of  a  camel-hair  brush  or 
feather.  After  waiting  a  few  minutes,  the  temperature  of  evaporation  may 
be  observed.  The  water  should  be  either  distilled  or  rain  water,  or  if  this  be 
not  procurable,  the  softest  pure  water  which  can  be  had.  The  water  vessel 
should  be  replenished  after,  or  some  little  time  before,  observing  ;  because 
observations  are  incorrect  if  made  while  the  water  is  either  colder  or  warmer 
than  the  air. 

In  connection  with  the  barometer,  the  Wet  and  Dry  Bulb  hygrometer  is 
very  useful,  not  only  on  land,  but  especially  at  sea,  where  other  kinds  of 
hygrometers  cannot  be  practically  used.  A  fall  in  the  Barometer  is  indicative 
of  coming  wind  or  rain ;  if  the  hygrometer  shows  increasing  dampness  by 
the  difference  of  the  readings  becoming  smaller, — rain  may  be  anticipated. 
On  the  contrary,  if  the  hygrometer  shows  continuing  or  increasing  dryness,  a 
stronger  wind  is  probable,  without  rain. 

The  Hygrometer  is  eminently  useful  in  regulating  the  moisture  of  the 
air  of  apartments  ;  a  difference  in  the  thermometer  readings  of  from  5°  to  8° 
being  considered  healthy.  Many  diseases  require  that  the  temperature  and 
humidity  of  the  air  which  the  invalid  breathes  should  be  very  carefully 
regulated.  In  a  room,  the  hygrometer  should  be  placed  away  from  the  fire, 
but  not  exposed  to  draughts  of  air. 



FIG.  87. 

103.  Negretti  and  Zambra's  Self-Kecording  Hygrometer,  fig.  87. 
The  Thermometers  in  this  Hygrometer  are  similar  in  construction  to  those  used 
in  Negretti  and  Zambra's  Patent  Hourly  Recording  Thermometric  Apparatus. 
No.  64,  Page  55.  It  will  be  seen  by  the  drawing  (fig.  87)  that  two 
Thermometers  are,  with  a  Water  Cistern,  mounted  upon  a  metal  frame  in; 
such  a  manner  that  they  will  fall  over  and  become  inverted  from  the  joint 
action  of  a  Clock  and  Galvanic  Battery. 

The  most  important  improvement  in  this  Self- Recording  Hygrometer  is 
that  it  can  be  freely  exposed  at  any  distance  from  the  regulating  clock.  Our 
wood  engraving  exhibits  the  Clock,  A,  with  an  adjusting  index  upon  its  dial, 
enabling  the  observer  to  arrange  the  release  of  the  detent,  B,  at  any  appointed 
time,  thus  allowing  the  frame  supporting  the  Hygrometer  to  turn  over,  and 
by  inverting  the  Thermometers  record  the  temperature  of  both  the  Wet  and 
Dry  bulb  instruments  at  the  moment. 

The  escapement  is  an  Electro  Magnet,  seen  at  B,  in  connection  with  a 
Galvanic  Battery,  B,  the  Clock  at  C  and  C,  and  the  Wire  A  and  A.  At  the 
arranged  time  the  circuit  is  completed  by  the  clock,  and  the  electrical  current 
acting  upon  the  soft  iron  magnet  releases  the  detent  and  the  Hygrometer 
turns  over. 

The  instrument  is  re-set  for  another  observation,  by  turning  back  the 
frame  with  the  Thermometers  into  its  original  vertical  position  (as  shown  in 
the  engraving)  and  by  adjusting  the  index  of  the  Clock.  Price  £10  10  0 

The  peculiar  construction  of  the  two  Thermometers  is  fully  described 
on  page  63,  and  fig.  71. 

45,    COKNHILL,    E.O.,    AND    122,   BEGENT    STREET,    W.,    LONDON. 


FIG.  88. 

FIG.  89. 

FIG.  91. 

FIG.  90. 
104     Screens  for  Thermometers  and  Hygrometers-. 



FiG.   92. 

104.  Beckley's  Thermograph  and  Eecording  Hygrometer.^— As 
recommended  by  the  Meteorological  Committee  of  the  Boyal  Society  for  pro- 
ducing Photographic  records  of  the  variations  of  temperature  and  moisture 
in  the  atmosphere. 

In  the  engraving  (fig  92)  the  Wet  and  Dry  Bulb  Thermometers  are  shown  at 
W  and  T.  freely  exposed  to  the  external  atmosphere,  at  H  is  a  screw  for  adjusting 
these  Thermometers ;  C  is  an  accurate  clock  for  rotating  the  cylinder  D  (upon 
which  is  stretched  the  sensitised  photographic  paper)  once  in  48  hours ;  G  G 
are  gas  lamps,  the  rays  of  light  from  them  being  concentrated  by  two  condensers, 
E  E,  upon  reflectors  M  M  and  thence  projected  by  the  Photographic  Combination 
Lenses  P  P,  through  perforated  screens  and  the  air  bubbles  in  the  tubes  of  the 
Thermometers  upon  the  prepared  paper.  Upon  the  drum  D  the  movements  of 
the  air  bubble  in  both  tubes  are  hereby  recorded  with  precision,  a  screen  in 
connection  with  the  clock  movement  is  arranged  to  intercept  the  light  for  4 
minutes  every  two  hours,  this  producing  white  lines  (time  spaces)  upon  the 
paper  when  the  record  is  developed. 

The  room  in  which  the  Thermograph  is  placed  should  be  most  carefully 
darkened  when  the  apparatus  is  in  action. 

Price,  £125,  complete  with  two  Standard  Thermometers,  two  Bent  Thermometers, 
Clock  Movement,  Sec.,  fyc..  complete,  made  to  order. 



105.  It  is  hardly  possibly  to  over-estimate  the  value  and  importance  of 
carefully  compiled  statistics  of  the  Rainfall.  The  two  great  sanitary  questions 
of  the  day,  viz.,  the  Water  supply  and  Sewage  of  large  towns,  are  in  a 
very  great  measure  connected  with  the  amount  of  rain  falling  during  a  given 
period,  and  reliable  particulars  of  the  rainfall  are  specially  valuable  both  to 
the  Civil  and  Hydraulic  Engineer. 

The  Farmer  and  commercial  Financier  are  also  both  deeply  interested  in 
the  results  of  a  probable  dry  or  wet  season  influencing  the  growth,  amount,  and 
value  of  various  crops  and  produce  of  the  earth.  We  subjoin  a  few  facts  we 
think  may  prove  useful  and  interesting. 

Fall  of  Rain  at  the  Royal  Observatory,  Greenwich. 

Taking  December,  January,  and  February  as  the  winter  months ;  March, 
April,  and  May  as  the  spring  months  ;  June,  July,  and  August  as  the  summer 
months ;  September,  October,  and  November  as  the  autumn  months,  the 
quantities  which  fell  in  the  different  seasons  were  as  follows : 









Winter      . 
Summer    . 
Autumn    . 










Total  . 








The  quantity  of  rain  which  fell  at  the  Royal  Engineers'  stations  during 

the  year  1853-4,  was  as  follows : 

St.  John's 
Malta   . 


Barbadoes    . 
Mauritius     . 
Fremantle    . 
New  Zealand 


Lincoln  is  the  dryest  recorded  station  in  England,  the  mean  annual  rain- 
full  being  20  inches.  The  wettest  recorded  station  is  Stye,  at  the  head  of 
Borrowdale  in  Cumberland,  where  the  mean  annual  rainfall  amounts  to  165 
inches.  A  fall  of  rain  measuring  a  tenth  of  an  inch  in  depth  is  equal  to  a 
deposit  of  about  forty  hogsheads  per  acre. 



106.  From  the  observations  made  at  the  Royal  Observatory  at  Greenwich, 
the  fact  is  clearly  established  that  in  the  lower  regions  of  the  atmosphere,  the 
quantity  of  rain  which  falls  diminishes  with  the  altitude  above  the  ground. 

The  height  for  placing  the  receiving  surface  of  a  rain  gauge  is  somewhat 
open  to  a  difference  of  opinion.  Mr.  Glaisher's  gauge  is  directed  to  be  **  half 
sunk  in  the  ground."  This  would  place  the  edge  of  the  gauge  about  8  inches 
from  the  surface  of  the  ground.  Mr.  Symons  gives  12  inches  as  most  correct, 
10  inches  as  a  mean  between  these  will  be  perhaps  the  best  to  adopt.  Rain 
gauges  should  be  placed  on  a  level  piece  of  ground,  and  not  on  a  slope  or 
terrace,  away  from  walls  or  trees,  as  many  feet  from  their  base  as  their  height, 
the  edge  of  the  funnel  should  be  set  quite  level.  Unless  for  special  observa- 
tions Rain  Gauges  should  not  be  placed  on  roofs  or  any  very  elevated  position. 
It  is  very  important  that  Rain  Gauges  be  occasionally  examined  to  see  that 
the  Receiving  Funnel  be  not  choked  up  by  dust  or  leaves,  and  that  at  very  wet 
stations  the  receiving  portion  of  this  Gauge  be  sufficiently  large  to  hold  any 
possible  rainfall ; — even  the  probable  occurrence  of  a  water-spout  might  be 
provided  for  in  hilly  or  very  exposed  situations.  Gauges  should  be  well 
supported  to  prevent  their  being  knocked  down  or  blown  over  by  the  wind, 
and  after  «riow  or  frost  the  gauges  should  be  placed  in  a  warm  room  until  the 
collected  contents  are  melted  and  can  be  measured.  In  measuring  off  the 
quantity  of  collected  rain,  the  graduated  glass  should  be  held  quite  upright, 
and  the  reading  taken  midway  between  the  two  apparent  surfaces  of  the  water. 
The  rain  should  never  be  collected  in  the  graduated  measure,  especially  in 
winter,  to  avoid  risk  of  breakage  by  frost. 

107  Measurement  of  Rain.  The  Rain  Gauge  should  be  examined 
every  day,  at  nine  a.m.,  and  the  amount  of  water  collected  by  it  entered  in  the 
register,  as  having  fallen  on  the  previous  day  ;  for  if  we  measure  at  nine  a.m. 
to-day,  it  is  probable,  under  ordinary  conditions,  that  more  of  the  Rain 
collected  by  the  Gauge  will  have  fallen  during  the  fifteen  hours  of  the  previous 
day  up  to  midnight  than  during  the  nine  hours  extending  from  midnight  to 
nine  o'clock  of  the  following  morning. 

A  vast  amount  of  interesting  and  most  valuable  information  respecting 
Rain  Gauges  and  the  Rainfall  will  be  found  in  Negretti  and  Zambra's  Treatise 
on  Meteorological  Instruments,  and  Mr.  G.  J.  Simons'  eminently  useful 
publications  as  enumerated  in  our  list  of  books  at  the  end  of  this  section. 

45,   CORNHILL,    B.C.,    AND    122,    REGENT   STREET,   W.,    LONDON.  83 


FIG.  93. 

FIG   94. 

FIG.  95 

108.  Howard's  Rain  Gauge,*  (fig.  93).     The  simplest  form  of  the  in- 
strument constructed  'and  used  by  the  celebrated  meteorological  writer,  Luke 
Howard,  from  whom  it  derives  its  name ;  it  has  a  5-inch  Copper  Funnel,  with 
a  turned  brass  Rim,  fitted  to  a  stoneware  or  glass  bottle,  with  a  glass  graduated 
measure  divided  to  hundredths  of  an  inch.  Price,    £0  10    6 

109.  Symons'   Rain   Gauge,    (fig.    94).     This  instrument  has  a  glass 
receiving  bottle  protected  by  a  metal  case,  with  openings  at  the  side  for  the 
convenience  of  observing  the  collected  rainfall  without  disturbing  the  frame, 
which  is  firmly  supported  in  the  ground  by  strong  spikes.     The  measure  holds 
half  an  inch  of  rain  for  a  5-inch  area  subdivided  into  hundredths. 

Price,  with  graduated  measure   .        .  £0  10    6 

Ditto,  in  Copper 0  15    0 

See  also  Symons1  Snorvdon  Rain  Gauge,  No.  118,  Page  85. 

110.  Glaisher's  Rain  Gauge,  (fig.  96). — This  gauge  is  eight  inches 
diameter,  and  arranged  for  the  reception  of  the  water  only  which  falls  upon 
its  receiving  surface,  and  for  the  prevention  of  loss  by  evaporation.     The  rain 
is   first  collected   in   a   funnel,   the   receiving   surface  of  which  is  accurately 

*  Pluviometer,  Ombrometer,  Udometer. 

G    2 



FlQ.  96. 

FIG.  97. 

turned  in  a  lathe,  and  terminated  at  its  lower  extremity  in  a  bent  tube  of 
small  aperture,  in  which  the  last  few  drops  of  rain  remain  as  shown  in  the 
engraving.  The  glass  receiving  vessel  is  graduated  to  hundred ths  of  inches 
according  to  the  calculated  weight  of  water,  as  determined  by  the  area  of  the 
receiving  surface.  In  use,  the  gauge  is  partly  sunk  below  the  surface  of  the 
soil,  so  that  the  receiving  surface  is  about  eight  inches  above  it.  Thus  situated, 
no  water  escapes  by  evaporation  in  any  month  of  the  year.  If  placed 
differently,  the  readings  must  be  taken  daily. 

Price t  in  Japanned  Tin     .  £1     1     0 

in  Copper        .         .     1  10    0 

RECEIVING  VESSEL  FOE  GLAISHER'S  GAUGE. — Price,  in  Japanned  Tin  or  Copper,  2s.  <k  3s.  6d. 

As  some  meteorologists  have  objected  that  the  curved  tube  at  the  base  of 
the  funnel  is  liable  to  be  choked  up  with  dust,  Messrs.  Negretti  and  Zambra,  if 
desired,  supply  these  Rain  Gauges  with  a  straight  tube  of  sufficient  length  to 
reach  very  nearly  the  bottom  of  the  receiving  vessel,  thus  obviating  this  diffi- 
culty, and  at  the  same  time  preventing  evaporation. 

111.  Glashier's  Rain  Gauge,  with  extra  large  receiving  vessel,  mounted 
with  a  convenient  tap  for  drawing  off  the  water,  suited  for  Tropical  countries 
or  stations  where  there  is  an  excessive  rainfall.  Price,  in  Copper,  £330 

The  8-inch  Glaisher's  and  the  Meteorological  office  Rain  Gauges  are  now 
considered  by  scientific  men  the  best,  and  consequently  are  almost  universally 
adopted  as  Standard  instruments,  but  at  the  same  time  we  would  observe  that 
most  valuable  results  have  been  obtained  by  the  use  of  Mr.  Symons'  5-inch 
gauge  in  many  parts  of  the  United  Kingdom. 

45,    CORNHILL,    E.G.,    AND    122,    BEGENT    STEEET,    W.,    LONDON.  85 

112.  Rain  Gauge  (fig  97),  having  a  receiving  surface  of  12  inches  diameter, 
arid  graduated  glass  tube  divided  to  inches,  tenths,  and  hundredths  of  an  inch, 
showing  by  simple  inspection,   without  the  use  of  a  graduated  measure,  the 
amount  of  rain  fallen.     In  japanned  metal,  with  tap  for  emptying  the  gauge. 

Price    .        .        .       £2  10    0         Ditto,  ditto,  in  Copper     .        3  10    0 

113.  Rain  Gauge,  a  similar  but  rougher  form  of  No.  112,  without  brass 
mountings,  and  instead  of  the  graduated  glass  tube,  it  is  fitted  with  a  boxwood 
scale,  attached  to  a  metal  float  inside  the  gauge,  on  which  can  be  read  off,  by 
simple  inspection,  the  amount  of  rain  fallen.  Price,  complete,  £220 

The  Rain  Gauges  (Nos.  112  and    113),  are  not  suitable  for  measuring 
small  quantities,  but  are  useful  where  the  rainfall  is  excessive. 

1 14.  Admiral  FitzRoy's  Rain  Gauge,  with  graduated  glass  dipping  tube, 
steadying  rods  or  supports,  and  frame,  now  very  rarely  used. 

Price,  in  Stout  Copper     £330 

115.  Pocket  Rain  Gauges,  with  3-inch  receiving  surface  and  correspond- 
ing measuring  glasses,  have  been  made  by  Messrs.  Negretti  and  Zambra,  but 
they  cannot  be  recommended. 

116.  Square  Rain  Gauge,  having  a  receiving  surface  of  10  inches  by  10 
inches,  and  about  L2  inches  in  height,  made  of  stout  copper — with  a  graduated 
glass  measure  divided  into  one  hundredths  of  an  inch,  as  described  in  Col.  Sir  H. 
James's  instructions  for  taking  meteorological  observations  for  the  use  of  the 
Royal  Engineers  ;  the  Gauge  is  shown  partly  in  section,  (fig  98.)  Price,  £2  10    0 

117.  Meteorological  Office  Rain  Gauge.  Our  woodcut  (fig.  99.)  shows 
a  recent  form  of  8-inch  Rain  Gauge  introduced  and  recommended  by  the  London 
Meteorological  Office.     It  will  been  seen  that  essentially  this  form  of  gauge  is 
the  same  as  Glaisher's,  but  with  an  additional  vertical  cylinder  about   6  inches 
above  the  funnel — its  use  is  to  prevent  in  splashing  and  also  most  especially  to 
collect  and  measure  Snow.  Price,  with  graduated  measure,  in  Japanned  Metal  £220 

Ditto  in  Copper          .        . 2  15    0 

118.  The  Snowdon  Rain  Gauge.     Mr.  Symons  has  made  some  improve- 
ments in  the  arrangement  of  his  Gauge,  these  are  chiefly  the  addition  of  a 
vertical  cylinder  above  the  funnel  and  doing  away  with  the  openings  in  the 
external  case  enclosing  the  receiving   bottle  ;    also   Mr.   S.    advises  that  the 
gauge  be  almost  entirely  plunged  below  the  surface  of  the  earth  as  a  protection 
from  evaporation  by  heat,  and  breakage  by  frost — another  advantage  of  the 
close  cylinder  is  that  should  the  collecting  bottle  be  broken  by  frost  or  other- 
wise its  contents  will  be  saved  to  the  observer.     The  form  of  this  Gauge  is  that 
of  fig.  95.  with  a  collecting  funnel  and  cylinder  of  5  inches  diameter.     This 
instrument  is  named  by  Mr.  Symons  the  Snowdon  Rain  Gauge. 

Price,  complete  in  Galvanised  Metal,  with  graduated  measure       .  £0  12    6 
Ditto,  ditto  in  Copper  .        ,        .        .150 
Mr  Symons'  Certificate  for  either  of  the  above,  2s.  6d. 






TIG.  99. 


119.  Negretti  and  Zambra's  Tropical  Rain  Gauge,  similar  in  form  to 
No.  99,  but  of  extra  large  size,  to  hold  50  inches   of  rain,  with  a  metal  tap  for 
drawing  off  the  collected  water. 

Price,  complete  with  receiving  vessel  and  graduated  measuring 

jar  in  japanned  metal £2  10    0 

Ditto  Ditto  in  Stout  Copper      .        .        .        .350 

120.  Crossley's  Registering  Rain  Gauge  (fig.  100.)  is  a  10-inch  square 
guage,  the  receiving  area  being  equal  to  100  superficial  inches.     The  water  col- 
lected by  the  funnel  passes  down  a  tube  to  a  vibrating  bucket  connected  with 
and  giving  movement  to   a  train  of  wheels  communicating  with  three  dials 
recording  the  amount  of  rain  passing  through  the  gauge,  in  inches,  tenths,  and 
hundredths.     The   mechanism  is    simple,    and   if  occasionally   examined   and 
kept  clean  it  will  give  a  faithful  record  to  -^-th  of  an  inch  depth  of  rain.     A 
small  test  measure,  holding  5  cubic  inches  of  water,  is  sent  with  each  instru- 
ment for  the  purpose  of  testing  and    correcting  the  gauge,  and    full  printed 
instructions   for    fixing,    reading    off    the  dials,    &c.,     &c.,    accompany    each 
instrument.     Under  careful  management  this  registering  gauge  will  be  found 
very  useful.  Price,  £4  12    0 

Great  care  should  be  taken  to  prevent  the  edge  of  the  collecting  or 
receiving  funnels  of  Rain  Gauges  being  bent  or  dented,  for  should  the  area  be 
not  a  true  circle  the  full  amount  of  rain  will  not  be  collected.  Circular  Rain 
Gauges  are  preferred  to  Square  ones,  the  latter  being  more  liable  to  get  out  of 
shape  than  the  former. 

45,  COENHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON. 

FIG.  100. 

121.  Symons'  Storm  Rain  Gauge,  (fig.  101).  This 
instrument  the  inventor  states  he  constructed,  not  as  a 
standard  or  thoroughly  accurate  instrument,  but  as  very 
convenient  for  observing  the  rate  of  rainfall  minute  by 
minute  without  either  measuring  or  going  out  of  doors. 
The  area  of  the  funnel  as  compared  with  that  of  the 
glass  tube  is  so  large  that  an  inch  of  rain  is  about  2  feet 
long  on  the  tube,  therefore,  as  each  tenth  of  an  inch  is 
about  3  inches  long,  the  water  can  be  seen  gradually 
rising  in  the  tube  as  the  rain  continues,  and  the  quantity 
FIG.  101.  in  any  interval,  however  short,  may  be  easily  noted. 

In  order  to  facilitate  reading  at  a  distance  floats  are  placed  in  each  tube,  and 
these  being  white  while  the  board  is  black  are  clearly  visible  at  a  great  distance. 
Each  division  on  the  scale  is  a  tenth  of  an  inch,  and  it  will  be  seen  that  the 
first  being  filled  up  to  the  top  line  (i.e.,  ten  tenths,  or  one  inch)  the  rain  flows 
into  the  second  and  that  float  begins  to  rise  until  two  inches  of  rain  have  fallen. 
The  Gauge  is  emptied  by  turning  the  button  (A)  and  then  inverting  the 
Gauge,  the  floats  cannot  fall  out.  In  frosty  weather  it  is  advisable  to  empty 
out  all  water  from  the  Gauge  and  place  a  cover  over  the  collecting  funnel. 

Price  for  Symons'  Storm  Kain  Gauge    £220 

A  larger  form  of  Registering  Rain  Gauge  (Pluviograph)  will  be  described 
in  connection  with  Osier's  Anemometer. 

122.  The  measurement  of  Snow  or  Hail  isato  be  effected  by  thawing  the 
quantity  collected  in  the  funnel  of  the  rain  gauge,  and  measuring  the  water 
resulting  therefrom.  The  rain  gauge  recommended  by  the  Meteorological  Office 
(No.  99),  is  specially  contrived  and  adapted  for  this  purpose,  the  snow  or  hail 
collected  being  thawed  by  a  known  quantity  of  hot  water.  This  quantity 





being  subtracted  from  resulting  amount  of  water  will  give  the  value  of  the 
collected  snow  or  hail. 

"  It  is  generally  stated  that  a  foot  of  snow  gives  an  inch  of  water ;  so  that 
one-twelfth  of  the  depth  of  the  snow  in  inches  would  be  the  amount  of 
rain  corresponding  to  a  given  fall  of  snow.  This  estimate  is,  however, 
only  a  very  loose  approximation,  as  the  layer  of  snow  is  not  always  of  uniform 

|  |  123.     Bentley's     Snow- Melting    Bain 

Guage.     (fig.102  .)  A  difficulty  has  hitherto 

\  S  existed  in  the  exact  admeasurement  of  rainfall 

B3BBHHBEET IffiBHBHBH^     — v^z->  ^'e  necessity  of  leaving  snow,  sleet,  or 

hail,  whenever  they  occur,  in  the  Gauge  until 
they  can  be  melted  ;  the  ordinary  Gauge  not 
being  always  capable  of  containing  the  amount 
of  a  long-continued  fall  of  snow. 

This  apparatus  was  contrived  by  Mr.  R. 
Bent-ley,  at  Upton  (near  Windsor),  for  use  in 
connection  with  an  8-inch  Guage  situated  on 
a  roof  inaccessible  under  ordinary  circum- 
stances. On  reference  to  the  accompanying 
diagram,  it  will  be  seen  that  the  distinguish- 
ing feature  of  this  Gauge  is  the  melting  of 
any  snow  or  sleet  immediately  on  its  reception. 
This  arrangement  makes  it  very  useful  in 
connection  with  any  automatic  registering 
apparatus,  or  where  the  Gauge,  from  its  posi- 
tion, is  not  easily  accessible,  and  at  night. 

The  action  of  the  Gauge  is  briefly  thus  : 
The  rain  or  snow  fall  is  received  in  the  usual 
8-inch  funnel,  from  the  bottom  of  which  it  falls 
by  gravity  to  the  end  of  the  tube  (of  whatever 
length  that  may  be)  without  touching  the  sides. 
This  is  a  very  important  point,  and  is  gained 
FIG  102.  ky  fitting  a  short  guide-pipe,  of  some  six  inches 

in  length,  to  the  bottom  of  the  funnel,  and  by  the  internal  diameter  of  the  long 
tube  being  gradually  slightly  increased  in  proportion  to  the  length  of  the  tube. 
At  the  bottom  of  the  tube  (which  is  within  the  house)  is  placed  a  tap  and 
measuring-glass.  If  preferred,  the  tap  can  be  left  open  or  removed,  and  an 
automatic  recording  apparatus  substituted. 

By  the  side  of  the  main  tube,  but  sufficiently  distant  from  it  for  any  heat 
not  to  be  conveyed  sideways,  is  the  melting  tube.  The  hot  air  is  furnished  by 
a  gas  jet  or  lamp — or  even  a  candle  or  night-light — and  being  regulated  to  a 

45,    COBNH1LL,   E.G.,   AND   122,    REGENT   STREET,   W.,   LONDON.  89 

temperature  of  from  about  40°  to  46°  Fahrenheit,  by  the  thermometer  enclosed 
in  the  tube  (and  exposed  to  view  by  means  of  a  piece  of  glass  inlet),  ascends 
through  the  funnel,  and  gradually  melts  the  snow,  etc.,  as  it  falls  in.  Too 
high  a  temperature  should  not  be  employed,  as  being  conducive  to  evaporation. 

An  additional  protection  may  also  be  afforded  by  the  employment  of  a  self- 
acting  valve  midway  in  the  heating  tube,  to  expand  with  any  access  of  heat,  in 
so  doing  partly  to  close  the  way,  and  at  the  same  time  to  push  open  a  small 
trap-door,  letting  out  some  of  the  hot  air  and  admitting  some  cooler  air  from 
the  outside.  As  soon  as  the  proper  temperature  has  been  by  this  means 
restored,  the  valve  would  contract  into  its  normal  position.  This  arrangement, 
however,  owing  to  the  delicacy  of  the  adjustment,  is  very  apt  to  get  out 
of  order. 

Messrs.  Negretti  and  Zambra  construct  the  above  apparatus  to  order ;  but 
no  exact  prices  can  be  quoted,  as  the  cost  would  vary  greatly  according  to  the 
extent  and  nature  of  the  work  and  the  position  in  which  it  is  to  be  placed. 

A  small  piece  of  very  open  wire- work  might  be  placed  across  the  receiver, 
halfway  down,  in  case  of  leaves,  &c.,  falling  in.  In  the  construction  of  the 
Gauge,  Copper  should  be  employed. 

124.  Marine  Bain    Gauges.     Negretti  and  Zambra  have  constructed 
several  different  forms  of  Rain  Grange  for  use  on  board  of  ship.     One  arrange- 
ment having  gimbal  mountings  similiar  to  a  steering  compass  has  been  found  the 
best,  but  the  records  obtained  by  their  use  at  sea  have  been  unsatisfactory  and 
not  considered  of  any  scientific  value. 


125.  Mr.  R.  H.  Scott,  of  the  Meteorological  Office,  writing  on  this  subject, 
remarks  that  it  "is  one  of  very  great  importance,  especially  as   regards    its 
connection  with  Rainfall  and  Water  supply,  and  well  deserves  especial  atten- 
tion ;  but  it  cannot  as  yet  be  said  that  the  results  hitherto  obtained  merit  much 
confidence  as  regards  their  applicability  to  the  evaporation  occurring  in  nature, 
owing  to  the  exceptional  manner  in  which  the  observations  have  been  made." 

Atmometers  of  many  forms  have  been  invented  and  constructed,  both  in 
this  country  and  on  the  Continent,  but,  at  present,  nothing  satisfactory  has 
been  devised  ;  hence  the  difficulty  of  making  any  very  accurate  observations 
in  connection  with  evaporation  from  the  surface  of  water. 

126.  Evaporation  Gauge,  (fig.  103),  (Evaporometer),  for  showing  the 
amount  of  evaporation  from  the  earth's  surface.     This  gauge  consists  of  a  brass 
vessel,  of  eight  inches  diameter,  corresponding  with  Glaisher's  Gauge,  the  area 
or  evaporating  surface  of  which  is  accurately  determined ;  and  also  a  glass 
cylindrical  measure,  graduated  into  inches,  tenths,  and  hundredths  of  inches. 
In  use,  the  Evaporating  Gauge  is  nearly  filled  with  water,  the  quantity  having 
been  previously  measured  by  means  of  the  glass  cylinder  ;  it  is  then  placed  out 



FIG.  103. 

FIG.  104. 

of  doors,  freely  exposed  to  the  action  of  the  atmosphere ;  after  exposure,  the 
water  is  again  measured,  and  the  difference  between  the  first  and  second 
measurement  shows  the  amount  of  evaporation  that  has  taken  place.  If  rain 
has  fallen  during  the  exposure  of  the  evaporating  dish,  the  quantity  collected 
by  a  rain  gauge  must  be  deducted  from  the  amount  of  the  measured  contents 
of  the  evaporating  dish  when  the  observation  is  made.  The  wire  cage  round 
the  gauge  is  to  prevent  animals,  birds,  &c.,  from  drinking  the  water. 

Price,  with  Graduated  Measure        .        .        :         £136 

127.  Atmidometer*  (Dr.  Babington's),  fig.  104  for  measuring  the  evapo- 
ration from  water,  ice  or  snow.  Consists  of  an  oblong  hollow  bulb  of  glass  or 
copper,  beneath  which,  and  communicating  with  it  by  a  contracted  neck,  is  a 
second  globular  bulb,  duly  weighted  with  mercury  or  shot.  The  upper  bulb  is 
surmounted  by  a  small  glass  or  metal  stem,  having  a  scale  graduated  to  grains 
and  half-grains  ;  on  the  top  of  which  is  fixed  horizontally  a  shallow  metal  pan- 
The  bulbs  are  immersed  in  a  vessel  of  water  having  a  circular  hole  in  the  cover 
through  which  the  stem  rises.  Distilled  water  is  then  gradually  poured  into 
the  pan  above,  until  the  zero  of  the  stem  sinks  to  a  level  with  the  cover  of  the 
vessel.  Thus  adjusted,  as  the  water  in  the  pan  evaporates,  the  stem  ascends, 
and  the  amount  of  evaporation  is  indicated  in  grains.  This  instrument  affords 

*  M  r.  Scott  suggests  that  Leslie's  term  Atmidometer  is  more  classically  correct,  but  that  Atmometer 
has  the  advantage  of  being  shorter,  without  being  absolutely  incorrect, 

45,    COBNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  91 

a  means  of  measuring  evaporation  from    ice    or   snow.      An  adjustment  for 
temperature  is  necessary.  Price,    £220 

Ditto,  large  size  with  Copper  Tank      3  10    0 

128.  Glaisher's    Thermometer  Stand    (fig.  91).— The   Thermometer 
Stand  consists  of  a  horizontal  board  as  as  a  base,  of  a  vertical  board  projecting 
upwards  from  one  edge  of  the  horizontal  board,  and  of  two  parallel  inclined 
boards,  separated  from  each  other  by  blocks  of  three  inches  in  thickness  con- 
nected at  the  top  with  the  vertical  board,  and  at  the  bottom  with  the  horizontal 
board,  and  the  air  passes  freely  about  and  between  all  these  boards  ;  on  the  top  of 
the  inclined  boards  is  a  small  projecting  roof  to  prevent,  as  much  as  possible,  the 
rain  or  snow  falling  on  the  bulbs  of  the  instruments  which  are  mounted  on 
the  front  of  the  vertical  board.     The  bulbs  of  the  Thermometers,  &c.,  all  project 
below  the  edge  of  the  vertical  board,  in  order,  that  the  air  may  pass  freely  over 
them  from  all  directions.     The  whole   frame  is  constructed  to  revolve  on  an 
upright  post  firmly  fixed  to  the  ground,  as  .shown  in  the  engraving;  and  in 
use,  the  inclined  side  should  always  be  turned  towards  the  sun. 

Price,        .        .        .        £330 

129.  Stevenson's  Thermometer  Screen,  shown  in  fig.  90.     The  louvres 
in  this  arrangement  are   double,  sloping  in  opposite  directions,  so  that  whilst 
there  is  free  access  of  air  to  the  interior,  the  radiant  heat  and  rain  are  excluded. 
This  form  of   Screen  is  now  found  to  be  the  best  of  any  yet  invented,  for 
climates  similar  to  the  British  Islands ;  but  is  not  suitable  for  climates  subject 
to  great  extremes,  such  as  India  or  Canada. 

This  Screen  should  stand  on  open  ground  and  be  strongly  supported,  not 
under  the  shadow  of  trees  or  houses,  and  at  least  twenty  feet  from  any  wall,  and 
the  floor  of  the  screen  to  be  about  four  feet  above  the  ground.  The  door  of  the 
Screen  should  face  due  north.  Price  .  .  .  £330 

130.  Negretti  and  Zambra's  Set  of  Standard  Instruments  on  a  Screen. 
Includes  N.  and  Z's.   Patent   Standard  Maximum  Registering  Thermometer, 
Standard    Minimum   Registering  Thermometer,  and  Standard   Wet  and  Dry 
Bulb  Hygrometer,  Mounted  on  Mahogany  Board.  fig.  88.   £550 

Kew  Certificates  for  above        ...  10    0 

The  best  position  for  placing  the  Thermometer  Board  or  Screen  is  facing 
the  North,  at  about  five  feet  from  the  ground,  supported  firmly  to  prevent 
vibration  from  wind  and  away  from  all  walls  or  trees,  or  if  this  board  be 
supported  by  a  wall  it  should  be  well  blocked  out  from  it  at  least  8  or  12  inchea 
to  allow  a  free  current  of  air  to  circulate  behind  it. 


131.  Apparatus  for  Determining  Elevations  by  the 
Temperature  of  the  Boiling-point  of  Water. —  The 
Barometrical  Thermometer,  or  Hypsometrical  Apparatus,  is  an 
improved  form  of  Wollaston's  Apparatus  constructed  by  Negretti 
and  Zambra,  to  meet  the  requirements  of  travellers  in  circum- 
stances where  the  mercurial  barometer  cannot  be  conveniently 
employed.  The  instrument  is  very  portable,  and  affords  a  ready 
and  accurate  means  of  measuring  heights.  The  apparatus  is 
shown  in  section  (fig,  105).  It  consists  : — • 

First, — of  a  very  sensitive  thermometer,  about  12  inches 
long,  the  scale  ranging  from  180°  to  212°,  having  each  degree 
subdivided  so  as  to  show  distinctly  0°  1. 

Secondly, — a  metal  boiler  (c)  mounted  on  a  small  tripod  stand; 
from  the  boiler  proceeds  three  double  tubes  (E  E  E)  and  (D  D  D), 
open  at  the  top ;  screwed  on  the  top  of  the  boiler ;  the  outer 
tube  has  two  openings,  one  at  the  top,  through  which  the 
Thermometer  (E  E)  is  inserted,  passing  down  to  within  an 
inch  of  the  water  in  the  boiler,  and  supported  by  means  of  an 
india-rubber  washer,  as  shown  in  tig.  105  ; 
the  second  opening  forming  an  outlet 
for  the  steam,  as  shown  at  (G).  These 
double  tubes  are  now  constructed  to 
separate  at  the  joints  by  a  simple  slide 
fitting,  so  that  any  length  of  the 
Thermometer  Stem  can  be  made  visible 
varying  with  the  elevation  at  which  the  tubes  are  adjusted. 
The  object  of  the  double  tube  is  to  ensure  a  steady  boiling- 
point,  in  which  it  would  be  impossible  to  obtain  in  open  air- 
experiments,  were  only  a  single  tube  employed.  (A)  is  a 
metallic  spirit  lamp,  surrounded  with  wire  gauze  (s)  to  pre- 
vent the  flame  being  extinguished  when  experimenting  in  the 
open  air.*  The  whole  instrument  when  packed  in  a  leather 
case  for  travelling  is  shown  in  fig.  105*.  Each  instrument  is  FIG  105*. 
furnished  with  a  carefully  computed  set  of  tables,  from  which  may  be  obtained, 
by  an  easy  calculation,  the  elevation  corresponding  to  any  observed 
boiling-point  between  the  temperatures  of  180°  and  212°. 

FIG.  105. 

*  A  Russian  spirit  furnace,  surmounted  by  a  small  spirit  lamp,  is  sometimes  furnished.  The  object  of 
the  Russian  furnace  is  to  cause  the  water  to  boil  rapidly  ;  when  that  has  been  accomplished,  the  small 
lamp  is  lighted,  and  placed  over  the  blast  from  the  furnace,  which  it  extinguishes,  at  the  same  time  its 
flame  is  sufficient  to  keep  the  water  boiling. 

45,   COKNHILL,    E.G.,   AND    122,    EEGENT    STREET,   W.,    LONDON.  93 

To  use  the  Boiling  Point  Apparatus,  it  is  simply  necessary  to  pour  into  the 
boiler,  through  the  small  opening  (F)  on  its  surface,  a  sufficient  quantity  of 
water  to  fill  it  about  one- third,  and  afterwards  close  it  by  means  of  the 
screw  for  that  purpose  ;  the  lighted  spirit  lamp  is  then  applied,  and  when  the 
water  is  made  to  boil,  the  steam  rises,  surrounding  the  bulb  and  tube,  and 
descending  between  the  two  tubes,  issues  from  the  opening  at  (G.)  After  a 
few  seconds,  the  mercury  in  the  thermometer  will  rise  and  become  stationary  ; 
the  degree  indicated  by  it  must  then  be  noted,  when,  by  reference  to  the  tables, 
the  elevation  of  the  spot  where  the  experiment  has  been  performed  may  be 

The  Temperature  of  the  Air  should  be  observed  by  a  reliable  Thermometer 
at  the  same  time.  Price,  with  Spirit  Lamp,  in  Sling  Case,  £550 

Extra  Standard  Thermometer    .     1  10    0 
Extra  Thermometer  for  Air  Temperature    .    0  10    6 

The  following  table  expresses  very  nearly  the  elevation  in  feet  correspond- 
ing to  a  fall  of  18°  in  the  temperature  of  boiling  water  : — 

Boiling  Temperatures  Elevation  in  Feet 

between  for  each  Degree. 

2HQ  and  210° 520 

210    and  200 530 

200    and  190 •  550 

190    and  180 570 

Mule  for  computing  heights  from  observations  rvith  the  Boiling  Point  Apparatus  or  Mountain 

Thermometer,  by  Negretti  and  Zambrd's  Boiling  Point  Tables. 

From  Table  I.  take  out  the  heights  in  feet  corresponding  to  the  boiling-points  observed 
at  the  upper  and  lower  stations  respectively.  The  difference  between  these  two  numbers, 
multiplied  by  the  factor  in  Table  III.  for  the  mean  temperature  of  the  air,  is  the  difference 
in  height  required. 


At  upper  station,  boiling-point  =  187°'3  ;  temp,  of  air  =  26°. 
At  lower  station,  boiling-point  =  2100-4  ;  temp,  of  air  =  68°. 
Boiling-point  =  187°'3  ;  height  from  Table  I.  =  13495  feet. 
Boiling-point  =  210°  4  ;  height  from  Table  I.  =  905. 

Difference  =12590 

Mean  temp,  of  air  =  47°  ;  factor  from  Table  III.     1-033. 

Kequired  difference  between  the  two  stations  =  12590  X  1'033  =  13005  feet. 
To  determine  a  height  with  accuracy,  it  is  necessary  that  pure  water  should  be  used, 
distilled  water  if  possible,  and  a  similar  observation  should  be  made  at  the  same  time  at  a 
lower  station,  not  very  remote  laterally  from  the  upper,  and  both  should  be  many  times 
repeated.  When  such  observations  have  been  very  carefully  conducted,  the  height  of  the 
upper  station  above  the  lower  may  be  ascertained  with  great  precision,  as  has  been 
repeatedly  verified  by  subsequent  trigonometrical  measurement  of  elevations  so  determined. 
If  the  lower  station  be  at  the  sea  level,  the  absolute  height  of  the  upper  is  at  once  obtained. 


FlG.   106. 

132.  Negretti  and  Zambra's  New  Pocket  Boiling-Point  Apparatus, 
(fig.  106)  consists  of  a  small  globular  metal  boiler,  mounted  upon  a  metal  sup- 
port or  stand.     In  the  base  of  this  stand  is  formed  a  receptacle  for  holding  and 
burning  spirits  of  wine,  by  which  water  in  {he  boiler  is  rapidly  heated  up  to  the 
boiling-point.     On  the  top  of  the  boiler  is  a  tube  for  the  escape  of  steam  during 
the  operation,  and  on  one  side  is  seen  another  tube  (horizontal),  into  which 
is    inserted    one    of    Negretti   and   Zambra's    Patent   Maximum    Registering 
Thermometers,  very  finely   and  carefully    divided  upon  its  stem,  of  sufficient 
range  for  all  possible  elevations  to  be  ascertained  by  the  boiling-point  of  water. 

The  boiler  having  been  charged  with  a  small  quantity  of  water,  and  the 
receptacle  filled  with  sufficient  spirit,  the  boiler  is  placed  upon  its  support 
above  the  burning  alcohol,  with  the  Thermometer  bulb  inserted  into  the  side 
tube.  In  a  few  minutes  the  boiling  point  will  be  attained,  and  the  mercury  in 
the  Thermometer  will  rise  to  this  point,  and  remain  in  the  tube  until  it  is 
convenient  to  note  the  temperature  thus  obtained. 

If,  after  the  experiment  has  been  made,  the  Thermometer  be  carefully 
withdrawn  from  the  boiler,  and  carried  with  the  ~bulb-end  uppermost,  the  record 
of  the  temperature  may  be  read  off  hours,  or  even  days,  afterwards.  The 
advantages  of  this  apparatus  are  great  simplicity,  rapidity  in  use,  and 

Price,  in  a  portable  case,  with  an  extra  Thermometer  for  Air  Temperatures,       £300 

133.  Pocket  Hypsometric  Apparatus,  as  constructed  by  Negretti  and 
Zambra  for  Dr  J.  D.  Hooker,  of  a  very  simple  and  conveniently  portable  form, 
with  one  corrected  Thermometer.     Suited  for  rough  exploring  expeditions. 

£2  10    0 

45,   CORNHILL,    E.G.,   AND    122,    EBGENT   STREET,    W.,    LONDON.  95 



FIG.  107. 

THE  records  obtained  by  the  use  of  various  forms  of  Anemometers  are  equally 
interesting  and  valuable. 

The  amount  of  pressure  and  velocity  of  the  wind  are  now  registered 
with  such  precision,  that  it  enables  Millwrights  and  Engineers  to  make  their 
calculations  and  arrange  their  machinery  in  accordance  with  the  amount  of 
work  required  to  be  done,  and  also  to  test  and  compare  the  expected  with  the 
actual  results. 

Meteorologists  are  equally  interested  in  Anemometer  records.  The  points 
of  direction  and  the  duration  of  the  wind  in  particular  quarters  and  seasons 
have  very  much  to  do  with  the  Rainfall  and  Evaporation  in  different  countries 
and  localities.  The  late  Admiral  FitzRoy  in  his  Weather  Manual  repeatedly 
indicates  the  great  importance  of  careful  observations  on  the  various  phenomena 
of  the  wind  in  connection  with  Marine  and  Sea  Coast  Meteorology. 

134.  Wind  Vane,  for  indicating  the  direction  of  the  wind.  See  next  page. 
It  is  important  to  note  that   the  North   point   of  the  Vane   should   be 

carefully  adjusted  to  the  Geographical  or  true  North,  and  not   to  the  Magnetic 
North.     See  Compass  Variations  in  Appendix  at  the  end  df  the  volume. 

135.  Anemoscope. — Dr.  Halleur's  Portable  Wind  Vane  and  Magnetic 
Compass,  for  showing  the  direction  of  the  wind  to  half  a  point  of  the  compass. 
This  instrument  is  very  similar  in  form  and  size  to  Lind's  Wind  Guage,  shown 
on  page  98.  Fig  109.  Price    £250 



FIG.  A. 

FIG.  B. 

136.  NEGRETTI  &  ZAMBRA  construct  Wind 
Vanes  of  various  dimensions  and  designs  to  suit 
the  positions  in  which  they  are  to  be  placed,  the 
cost  varying  with  the  amount  of  work  and 
ornament  upon  them. 

As  Fig.  A.  2  feet  3  inches  high  .        .£150 

5  feet  .        .        .  ..3126 

As  Fig.  B.  4  feet  high    .        .  .         .330 

5  „       „       .         .  .         .        4  12     6 
As  Fig.  C.  3  feet  high           .  .        .       250 

6  „       „       .        .  .        .        550 

These  prices  do  not  include  fixing,  for  which 
special  estimates  will  be  furnished. 

These  Vanes  are  japanned  in  plain  colour  — 
Black,  Red,  Yellow  or  Blue.  Gilding  the  Vane 
and  Arrow  extra,  14/6.  Gilding  the  Direction 
Letters,  14/-. 

N.  &  Z.,  fit  up  Wind  Vanes  arranged  to  show  the  varying  direction  oi 
the  Wind  upon  a  Dial  in  the  interior  of  Mansions  or  Public  Offices.  The  cost 
for  erecting  such  Wind  Indicators  depending  much  on  the  height  of  the 
building,  and  the  position  in  which  the  Vane  is  to  be  placed,  no  positive  prices 
can  well  be  quoted  ;  estimates  given  upon  particulars  being  sent. 

Wind  Vanes  ore  frequently  fitted  upon  buildings  in  connection  with  Lightning 
Conductors,  particulars  will  be  found  in  another  section. 

45,    COKNHILL,    E.G.,   AND    122,    EEGENT    STREET,    W.,    LONDON.  97 

FIG.  108. 

137.  Wegretti  and  Zambra's  Improved  Pendulum  Anemometer 
invented  by  Dr.  Prestel  to  exhibit  at  any  moment  in  a  most  simple  manner  the 
direction  and  comparative  pressure  of  the  wind. 

By  the  action  of  the  peculiar  shaped  vane  A,  the  surface  of  the  swinging 
pressure  plate,  B,  is  always  kept  facing  the  point  from  which  the  wind  is 
blowing,  and  consequently  exposed  to  its  influence.  During  a  calm  the 
pendulous  plate,  B,  will  hang  quite  vertical  in  a  line  with  the  axis  of  the  vane 
plate  indicating  zero  or  calm.  As  the  wind  increases  in  force  the  pressure 
indicator  will  be  raised  to  various  points  between  1  and  10  of  the  vane. 

The  holes  are  drilled  through  the  plate  of  sufficient  size  to  be  plainly 
visible  at  a  considerable  height  from  the  ground ;  and  to  facilitate  the  reading, 
the  5  and  10  are  of  a  larger  conical  form,  so  that  the  position  of  the  pressure 
plate  can  be  quickly  observed. 

The  subjoined  table  gives  in  English  and  French  measures  the  value  of  the 
indications.  The  Metrical  scale  is  calculated  to  show  the  pressure  of  wind  in 
kilogrammes  on  the  square  meter,  and  the  English  scale  pounds  on  the  square 

foot.  • 

I.  II. 

Scale  of 
P.  A. 

in  Kilgr. 
on  S.  M. 




Description  of  Wind. 

Pressure  in 
Ibs.  on  the 
Sqre.  foot. 












Gentle  motion  of  air. 







Light  breeze. 







Fresh       „       (top  gallant  W.) 







Stiff         „       (strong  top  gallant  W.) 







Very  Stiff  breeze  (top  sail  W.) 








Strong  rushing  W.  (to  house  top  git.) 







Stormy  W.  (to  house  top  sails.) 


8.  . 




Gale  of  Wind. 






Strong  Gale. 














Negretti  and  Zambra  think  this  Anemometer  will  meet  a  want  often 
expressed  to  them,  viz.,  a  simple  self-acting  Wind-gauge ;  for  with  very  little 
more  mechanical  combination  than  a  common  direction  vane,  the  Pendulum 
Anemometer  will  give  sufficiently  accurate  results  for  unscientific  observers. 
It  has  also  the  advantages  of  extreme  simplicity,  for  beyond  a  little  oil  to  the 
moving  parts  and  an  occasional  coat  of  paint  for  protection,  it  does  not  require 
the  least  attention.  Price,  fig.  108,  £660 

The  simplest  mode  of  mounting  this  Anemometer  is  to  fib  it  on  the  top  of 
a  flag-staff  or  mast  30  to  40  feet  high,  well  sunk  in  the  ground,  strengthened 
and  supported  by  three  or  four  wire  rope  stays,  attached  to  small  sunk  posts  in 
the  earth ;  these  wire  ropes  might  be  used  as  Lightning  Conductors.  Arms 
with  the  letters  N.  E.  S.  and  W.  to  show  the  direction  of  the  wind  as  on  fig.  A 
page  96  can  be  placed  on  the  mast  below  the  Anemometer. 

138.  Lind's  Anemometer  or  Wind 
Gauge  (fig.  109),  invented  in  the  year  1775, 
for  observing  the  pressure  of  the  wind,  con- 
sists of  a  glass  syphon,  the  tubes  are  parallel 
to-  each  other,  and  each  tube  is  of  the  same 
diameter.  One  end  of  the  syphon  is  bent  at 
right  angles  to  the  general  direction  of  the 
tubes,  so  as  to  present  a  horizontal  opening 
to  the  action  of  the  wind.  A  graduated 
scale,  divided  to  inches  and  tenths,  is 
attached  to  the  syphon  tube,  reading  either 
way  from  a  zero  point  in  the  centre  of  the 
scale.  The  whole  instrument  is  mounted 
on  a  spindle,  surmounted  by  a  vane,  and  is 
moved  freely  in  any  direction  by  the  wind, 
always  presenting  the  open  end  of  the  tube 
towards  the  quarter  from  which  the  wind 
blows.  To  use  the  instrument  it  is  simply 
filled  up  to  the  zero  point  with  water,  and 
then  exposed  to  the  wind;  the  difference 
in  the  level  of  the  water  gives  the  ,force  of 
the  wind  in  inches  and  tenths,  by  adding 

FIG.  109.  together  the  amount  of  depression  in  one 

limb,  and  elevation  in  the  other,  the  sum  of  the  two  being  the  height  of  a  column 
of  water  which  the  wind  is  capable  of  sustaining  at  that  time.  At  the  base  of 
the  instrument  is  a  brass  plate,  upon  which  are  engraved  the  principal  points 
of  the  compass,  for  indicating  the  direction  of  the  wind.  Price,  £220 

The  bend  of  the  syphon  is  contracted  internally  to  diminish  the  jumping 
movement  of  the  water  produced  by  sudden  gusts  of  wind. 

45,    CORNHILL,   E.C.,    AND    122,    REGENT   STREET,    W.,    LONDON.  09 

No.  139.  Negretti  and  Zambra's  Registering  Lincl's  Anemometer. 
Several  modifications  of  Lind's  Wind  Gauge  have  at  various  times  been  in- 
vented by  Sir  W.  Snow  Harris,  Mr.  Wood  and  others,  with  a  view  to  make  ifc 
self-recording,  but  the  only  one  that  proves  satisfactory  in  actual  service,  is  an 
arrangement  manufactured  by  Negretti  and  Zambra  at  the  suggestion  of  Mr. 
Forbes,  of  Inverness.  The  improvement  consists  of  a  third  tube  of  the  same 
internal  diameter,  connected  by  a  bend  at  the  Zero  point  of  the  instrument, 
into  which  the  water  overflows  and  is  collected  from  the  leeward  tube  of  the 
syphon.  The  water  thus  collected  being  the  maximum  amount  of  depression 
produced  in  the  syphon  representing  the  extreme  force  of  the  wind. 

Table  showing  the  Force  of  wind  on  a  square  foot,  for  different 
heights  of  the  column  of  Water  in  Lind's  Wind-Gauge. 


Force  in  Ibs. 

Common  designation  of  such  Wind. 



A  Hurricane. 



A  violent  Storm. 



A  great  Storm. 



A  Storm. 



A  strong  Wind. 



A  high  Wind. 



A  brisk  Wind. 



A  fresh  Breeze. 



A  gentle  Breeze. 



A  Calm. 

Price,     £330 
140.     Improved   Portable   Air  Meter,  for  measuring  the  velocity  of 

currents  of  Air  in  Coal  Mines  and  Ventilators,  Flues,  &c.,  of  Public  Buildings, 

Hospital  and  Prison  Wards,  &c.,  &c.   (figs.  110  and  111.) 

By  means  of  this  Air  Meter,  the  rate  at  which  a  current  of  Air  is  moving 

can  be  ascertained  in  a  few  minutes.     The  Instrument  shows  from  one  foot  to 

ten  million  feet. 

The  long  hand  marks  up  to  100  feet ;  each  division  on  the  large  circle  represents  one 

foot  traversed  by  the  current  of  air.     In  setting  down  a  reading  of  the  hands,  the  long  hand 

takes  the  units  and  tens  places.    The  five  other  hands  follow  respectively. 


Millns.    100  thds.  10  thds.  thds.     hds.    long  hand. 

Places  the  hands  take  when  set  down  in  figures    00|0|0|OjO|00 
Reading  of  the  above  diagrams    ...  1      |     0     J     9  0      |      9  99 

In  setting  down  the  position  of  the  hands  observe  the  following  rule  : — No  hand  can 
mark  a  figure  unless  the  foregoing  hand  has  arrived  at  the  "  0."  For  example,  suppose  the 
long  hand  pointed  to  99,  the  hundreds'  hand  would  appear  to  point  to  a  figure,  but  it  could 
not  mark  the  figure  until  the  long  hand  pointed  to  the  zero.  The  same  rule  applies  to  all 
the  hands.  When  a  hand  appears  to  be  between  the  divisions,  write  down  the  lowest  figure 
next  the  hand. 

The  catch  on  the  rim  of  the  instrument  will  stop  or  allow  the  hands  to  run  without 
affecting  the  action  of  the  fans. 



FIG.  110.  FIG.  111. 

The  above  engraving  of  the  Dial  is  the  exact  size  of  the  Dial  of  the  Instrument. 

The  Meter  may  be  fi^ed  in  the  current  on  a  rod,  fitted  into  the  socket,  which  screws  into 
the  bottom  of  the  instrument. 

To  take  a  measurement  fix  the  position  of  the  hands  (by  moving  the  catch)  write  down 
the  reading,  and  place  the  Meter  in  the  current  of  air  to  be  measured.  Now  put  the 
hands  in  action  by  again  moving  the  catch  at  the  same  moment,  note  the  time  by  the 
second  hand  of  a  watch,  allow  the  fans  to  run  in  the  current  for  one  minute,  at  the  end  of 
which  time  again  put  the  hands  out  of  action,  and  again  read  their  position,  subtract  the 
first  reading  from  the  second,  and  the  result  gives  the  velocity  of  the  air  in  feet  per  minute 

The  Meter  may  be  allowed  to  run  ia  the  current  of  air  for  any  convenient  length  of 
time  ;  but,  if  for  longer  than  one  minute,  the  difference  of  the  first  and  second  readings 
must  be  divided  by  the  number  of  minutes  of  the  running.  This  gives  the  (uncorrected) 
velocity  of  air  for  one  minute. 

A  table  is  supplied  with  each  instrument,  showing  the  necessary  correction  for  friction, 
&c.,  at  various  velocities  per  minute.  In  the  -second  column  of  this  table  will  be  found  the 
correction  (opposite  the  velocity  shown  by  the  Meter  in  the  first  column).  This  correction' 
if  applied  to  a  measurement  of  more  than  one  minute,  must  be  multiplied  by  the  number  of 
minutes  of  the  measurement,  and  added  to  or  subtracted  from  (according  to  the  sign)  the 
difference  of  the  two  readings, 


Suppose  the  first  reading  to  be    . 

And  the  second  after  a  running  of  ten  minutes  is 



The  running  per  minute  would  be  .        .        ,        . 

Say  the  correction  for  580  shown  by  the  meter  per  minute  is 

The  real  or  corrected  velocity  per  minute  would  be 



45,    CORNHILL,    E.G.,    AND    122,    EEGENT    STREET,  '\V.,    LONDON. 


And  the  real  velocity  during  the  running  of  ten  minutes  is  6620  feet. 

The  measurement  of  the  current  of  air  in  feet  per  minute,  divided  by  88,  will  give  the 
measurement  or  velocity  in  miles  per  hour. 

NOTE. — In  taking  a  measurement  the  fans  must  always  face  the  wind,  and  care  should 
be  taken  not  to  bend  or  injure  them. 

Price  of  the  Improved  Air  Meter  in  a  neat  Box,  figs.  110  and  111      £440 

141.  Lowne's  Patent  Colliery  Air 
Meter  constructed  expressly  for  use  in  Coal 
Mines  or  Air  Shafts. 

The  improvements  consists  of — 1st, 
a  large  clear  Dial;  2nd,  the  Fan  is  con- 
structed of  a  light  and  anti-corrosive  material ; 
3rd,  the  Indicating  parts  are  perfectly  pro- 
tected from  dust  and  smoke  (this  is  done  by 
a  practical  mechanical  arrangement)  ;  and,  4th, 
a  Lever  is  placed  in  a  convenient  position,  to 
enable  the  observer  to  throw  the  Indicating 
"Wheels  in  or  out  of  gear  from  the  Fan, 
for  the  purpose  of  taking  short  ^observations 
with  accuracy-,  6-inch  Air  Meter,  as  fig.  112,  Price,  £4  10  0 

FIG.  112. 


Press  the  Lever  home  to  the  left  hand,  and  the  Fans  will  revolve  without  moving  the 
Registering  Works.  Now  take  a  careful  reading  of  the  instrument,  and  write  it  down  ; 
hold  the  Air  Meter  in  the  current  by  the  ring  at  the  top  of  the  Instrument  ;  allow  the  Fans 
to  run  freely  for  a  short  time.  Now  observe  the  Watch.  When  the  Second  Hand  reaches 
the  Minute,  press  the  Lever  to  the  right,  and  the  works  will  be  in  gear.  When  the  minute 
is  up,  again  press  the  Lever  to  the  left  hand,  to  throw  the  works  out  of  gear  ;  take  a  reading 
of  the  dial  and  write  it  down  above  the  first  reading,  subtract  the  first  reading  from  the 
second,  and  the  difference,  after  the  correction  is  added,  will  be  the  velocity  of  the  current 
in  feet  per  minute,  thus  : — 

Second  Reading 9,260 

First  Reading     .  8,920 

Add  Correction,  say — 

Rate  of  current 


380  feet  per  minute. 

For  measuring  currents  for  a  longer  space  of  time,  the  Air  Meter  should  be  suspended 
on  a  bar,  or  fixed  in  any  convenient  manner  in  the  current. 

The  Fans  must  always  face  the  current,  and  great  care  should  be  taken  never  to  stop 
them  suddenly. 


NE'GfefcTTl   AND   ZAMBEA,   HOLBOKtf  VIADUCT,    B.C., 

NOTE.— -Any  one  not  familiar  with  Metric  Dials  must  observe  that  the  figures  read 
rationally  :  thus,  if  the  feet  hand  is  at,  say,  nine,  the  tens  hand  will  be  near  the  figure  it  is 
approaching.  This  figure  must  not  be  taken,  but  the  previous  one  that  is  passed. 

Table  showing  the  number  of  miles  per  hour  at  velocities  per  minute. 

Feet  per 

Miles  per 

Feet  per 

Miles  pei 

Feet  per 

Miles  per 

























































"  When  inquiring  into  the  causes  of  air  currents,  either  from  or  within  drains,  it  was 
suggested  that  the  variable  flow  of  sewage  has  a  powerful  influence  on  the  air  within  the 
drain,  whilst  that  produced  by  rainfall  has  still  greater,  and  the  variations  of  temperature 
are  another  cause  of  displacement  and  renewal  of  drain  air.  A  series  of  observations  were 
taken  at  the  outlets  of  drains  by  the  Anemometer  at  the  point  of  connection  with  the 
sewer,  and  the  results  proved  that  up  and  down  currents  of  air  are  constantly  passing  to  and 
fro.  Whenever  an  up-current  issues  through  a  drain-opening  it  must  be  manifest  that  some 
of  the  inlets  of  such  drains  are  untrapped.  and  therefore  sewer  air  must  be  escaping  through 
such  untrapped  inlets,  to  the  danger  of  those  who  reside  in  the  house." 

142.     Biram's  Anemometers,  for  registering  the  velocity  of  currents  of 
air  in  mines,  &c.,  by  means  of  a  light  vane,  the  revolutions  of  which  are 
recorded  npon  a  dial  in  the  centre  of  the  instrument. 
12-in.,  £5     0     0;     6-in.,  £4    0     0;     4-in.,  £3     3     0;     2J-in.,  £2  10     0 

These  Anemometers  will  register  the  velocity  of  Air  through  any  passage 
of  a  Mine  or  Air  Shaft  in  which  they  are  placed. 

'For  the  purpose  of  trying  and  regulating  the  proportions  of  Air  to  the 
several  divisions  of  a  mine,  and  for  the  convenience  of  Overlookers,  the  three 
small  instruments,  6  inches,  4  inches,  and  2J-  inches,  are  recommended.  These 
sizes  will  also  be  found  convenient  for  use  in  large  gun  or  rifle  practice. 

To  ascertain  the  rate  at  which  air  is    moving,  proceed  thus — suppose 
100  revolutions=200  feet  per  minute. 
88]  200  [2^27. 

Say  2J  miles  per  hour — 88  being  l-60th  of  a  mile. 

To  find  the  force  of  Wind,  multiply  the  square  of  the  velocity  of  the  wind 
in  feet  per  second  by  "0023. 

NOTE. — The  velocity  of  the  wind  in  feet  per  minute,  divided   by  88,  will 
give  the  velocity  in  miles  per  hour.     (See  above  example.) 

45,  COBNHILL,  E.C.,  AND  122,  REGENT  STREET,  W.,  LONDON. 


143.  New  Self-Timing 
Anemometer  (Patent).  This 
improved  instrument  dispenses 
with  the  use  of  a  watch.  By  hold- 
ing the  Anemometer  in  the  current 
of  air  to  be  measured  for  a  few 
seconds  it  will  correctly  indicate 
its  velocity  per  second. 

Price,  tig.  113.     £500 


This  instrument  is  held  up 
with  its  back  facing  the  current  of 
air  to  be  measured.  When  the 

.  113.  vanes    have   revolved   for    a    few 

seconds,  press  the  spring  button  at  A,  the  large  hand  then  indicates  feet  per 
second.  When  read  release  the  spring  button.  Should  the  velocity  be  such 
that  the  hand  travels  more  than  one  revolution,  then  read  the  inner  circle  of 
figures.  The  small  hand  shows  whether  the  outer  or  inner  circle  should 
be  read. 

NOTE. — As   every  instrument  is  graduated    at   each  unit  by  actual   experiment^    no 
allowance  has  to  be  made  for  friction. 

Feet  per 

Feet  per 

Miles  per 

Force  in 
Ibs  per 
square  foot. 






Hardly  perceptible. 






1    Just  perceptible. 










>    Gentle  breeze. 











i    Pleasant  breeze. 





Brisk  gale. 





High  wind. 





Very  high  wind. 










Great  storm. 















FIG.  114. 

144.  Robinson's  Anemometer. — Dr.  Robinson,  of  Armagh,  is  the  inventor 
of  this  very  useful  anemometer,  for  determining  the  horizontal  velocity  of  the 
wind.  It  was  first  used  in  1850,  in  the  meteorological  and  tidal  observations 
made  on  the  coast  of  Ireland  under  the  direction  of  the  Rev.  Dr.  Lloyd.  It  is 
represented  in  its  simplest  form  by  fig  114.  Four  hollow  hemispherical  cups 
AA,  are  extended  upon  strong  metal  arms,  with  their  concave  services  facing 
the  same  way  upon  a  vertical  axis,  B,  which  has  at  its  lower  extremity  an  end- 
less screw,  D.  The  axis  is  supported  and  strengthened  at  (7,  and  constructed 
so  as  turn  with  as  little  friction  as  possible.  The  endless  screw  on  the  vertical 
shaft  is  placed  in  gear  with  a  train  of  wheels  and  pinions.  Each  wheel  revolves 
past  a  fixed  index,  and  the  figures  and  graduations  are  marked  upon  the  wheels 

The  readings  on  the  dials  of  the  Anemometer  are  as  follows  :  one  complete 
» revolution  of  ihe  first  engraved  index- wheel  equals  -^  of  a  mile;  the  second,  I 
mile ;  the  third,  10  miles  ;  the  fourth,  100  miles ;  the  fifth  1,000  miles ;  neces- 
sarily in  noting  such  reading  it  must  be  done  backwards,  according  to  the 
indications  on  the  instrument. 

Dr.  Robinson  has  proved  by  theory  and  experiment  that  the  centre  of  any 
one  of  the  cups  mounted  as  fig.  114  revolves  with  one-third  of  the  wind's 
velocity.  Therefore  allowance  has  been  made  for  this  in  graduating  the  circles, 
and  a  true  reading  is  at  once  obtained.  Price,  fig.  114  £3  3  0  and  440 

145.  Robinson's  Anemometer.  Negretti  and  Zambra's  improved 
arrangement  for  recording  the  velocity  of  the  wind,  as  described  by  Colonel  Sir 
H.  James,  Royal  Engineers.  This  is  a  modified  form  of  the  Robinson 
instrument  previously  described,  our  engraving  (fig.  115)  will  show  the  general 
details  of  the  mechanism. 

.  It  consists  of  four  arms  at  the  end  of  which  there  are  four  light  hemis- 
pherical hollow  metal  cups,  the  concave  surfaces  facing  in  one  direction  and 
revolving  with  one-third  of  the  velocity  of  the  current  of  wind  acting  on  them. 
On  the  vertical  axis  which  carries  the  arms,  there  is  an  endless  screw,  which 
communicates  its  real  velocity  of  rotation  to  a  circular  dial. 

45,    CORNHILL,    B.C.,   AND   122,    REGENT   STREET,    W., 




FIG.  115. 

This  Anemometer  is  furnished  with  two  graduated  circles,  the  outer  one 
being  divided  into  five  miles  and  tenths  of  a  mile,  and  each  division  on  the 
inner  circle  represents  five  miles.  One  revolution  of  this  circle  recording  from 
five  to  five  hundred  and  five  miles.  The  fixed  pointer  or  index  recording  on  the 
outer  circle  miles  and  tenths  of  a  mile  to  five  miles  ;  and  the  moving  index 
records  every  five  miles  up  to  five  hundred.  If  for  example  the  movable  hand 
stands  between  15  and  20  on  the  inner  circle,  and  the  fixed  hand  indicates  3 
miles  and  five-tenths  the  length  of  the  current  of  air  which  has  passed  the 
station  is  equivalent  to  18  miles  and  five-tenths. 

The  velocity  of  the  wind  at  any  particular  moment  is  found  by  observing 
the  index  before  and  after  a  certain  interval  of  time  as  one  or  five  minutes,  and 
then  multiplying  the  rate  by  60  or  12  to  find  the  velocity  in  miles  per  hoar. 

The  pressure  in  Ibs.  per  square  foot  can  then  be  ascertained  by  reference  to 
tables  mentioned  in  our  list  of  books  at  the  end  of  this  Section.  A  mill-headed 
screw  at  the  back  of  the  instrument  (fig.  89)  turns  the  movable  index,  which 
should  be  brought  back  to  zero  after  the  observation  is  registered. 

Price,  fig.  115,     £4  10    0 

The  Anemometer  frame  is  arranged  for  screwing  on  the  instrument  to  a 
firmly-supported  post. 

146.  Robinson's  Anemometer,  (fig.  116).  This  drawing  shows  a  further 
improvement  in  the  recording  movement,  a  second  dial  being  added  for  the 
convenience  of  obtaining  extended  readings. 

The  left  hand  dial  of  this  Anemometer  is  divided  and  figured  exactly  the 
same  as  in  the  previously  described  instrument,  and  the  indications  read  off  in 
a  similar  manner.  The  second  dial  has  10  divisions,  each  of  these  divisions 
being  equal  to  505  miles,  which  is  sub-divided  by  the  readings  of  the  left  hand 
dial.  Price,  fig.  116,  6  15  0 



FIG   116. 

147.  Robinson's  Anemometer,  mounted  in  gimbals  for  Marine  Service. 
This  instrument  not  having  been  found  of  much  practical  value  will  only  be 
made  to  order. 

Robinson's  Anemometers  should  be  fixed  in  an  exposed  situation,  as  high 
above  ground  as  may  be  convenient  for  reading.  It  can  be  made  very  portable 
by  having  the  arms  which  carry  the  cups  being  fitted  to  unscrew  or  to  fold  down. 

148.  Whewell's    Self-registering   Anemometer,   for   recording    the 
amount  of  horizontal  movement  in  the  air,  with  the  direction,  for  twenty-four 
hours.     A  full  description  of  this  Anemometer  will  be  found  in  Negretti  and 
Zambra's  Treatise  on  Meteorological  Instruments.     It   is   now   rarely   used, 
Osier's  and  Beckley's  arrangements  having  been  found  more  practically  useful. 

Price,     £25     0    0 

Any  of  these  Anemometers  can  ~be  supplied  metrically  divided  if  desired. 

149.  Osier's    Self-registering     Anemometer    and     Rain    Gauge 
(fig.  117).     This  improved  arrangement  of  Anemometer  was  shown  by  Messrs. 
Negretti  and  Zambra  at  the  International  Exhibition,  1862,  having  Robinson's 
Cup  Anemometer  added  to  it,  so  that  the  pressure  and  velocity  appear  on  the 
same  sheet  on  which  a  line,  an  inch  in  length,  is  recorded  at  every  10  miles. 
The  Improved  Anemometer  shows  the  Direction,  Pressure,  and  Velocity  of  the 
Wind,  also  the  amount  of  Rainfall  upon  one  Sheet  of  paper.     Our  woodcut  is 
not  given  as  an  actual  working  drawing  of  Osier's  Anemometer,  but  simply  to 
exhibit   the  relative  position    of  its  several   parts.     The   mechanism  may  be 
variously  modified,  but  the  following  is  a  description  of  the  most  recent  and 
improved  arrangement. 

45,    COBNHILL,   E.G.,   AND    122,    EEGENT   STREET,   W.,   LONDON.  107 

FIG,  117. 

Osier's  Self-registering   Anemometer  and 
Rain  Gauge. 

Osier's  instrument  (fig.  ]  17)  consists  of  the  vane,  V9  of  a  wedge-shaped  form, 
which  is  found  to  answer  better  than  a  flat  vane ;  for  the  latter  is  always  in  a 
neutral  line,  and  is  therefore  not  sufficiently  sensitive.  At  the  lower  end  of  the 
tube,  2T,  is  a  small  pinion,  working  in  a  rack,  r,  which  is  moved  backwards 


and  forwards  as  the  wind  alters  the  position  of  the  vane.  To  this  rack  a  pencil, 
#,  is  attached,  which  marks  the  direction  of  the  wind  on  a  ruled  paper,  placed 
horizontally  beneath,  and  so  adjusted  as  to  progress  at  the  rate  of  half  an  inch 
per  hour,  by  means  of  a  simple  contrivance  connecting  it  with  a  clock,  which 
carries  the  registering  paper  forward  by  one  of  the  wheels  working  into  a  rack 
attached  to  the  frame.  The  paper  is  shown  in  the  illustration  upon  the  table 
of  the  instrument. 

The  pressure  plate,  F,  for  ascertaining  the  force  of  the  wind,  is  one  foot 
square,  placed  immediately  beneath  the  vane  ;  it  is  supported  by  light  bars, 
running  horizontally  on  friction  rollers,  and  communicating  with  springs, 
1,  2,  3,  so  that  the  plate,  when  affected  by  the  pressure  of  the  wind,  acts  upon 
them,  and  they  transfer  such  action  to  a  copper  chain  passing  down  the 
interior  of  the  direction  tube,  and  over  a  pulley  at  the  bottom.  A  light  copper 
wire  connects  this  chain  with  a  spring  lever,  y  y,  carrying  a  pencil  which 
records  the  pressure  upon  the  paper  below.  Mr.  Osier  prefers  a  spring  to  any 
other  means  for  ascertaining  the  force  of  the  wind,  because  it  is  of  the  highest 
importance  to  have  as  little  matter  in  motion  as  possible,  otherwise  the 
momentum  acquired  will  cause  the  pressure  plate  to  give  very  erroneous 
indications.  The  pressure  plate  is  as  light  as  is  consistent  with  strength. 
It  is  kept  before  the  wind  by  the  vane,  and  is  urged  out  by  three  or  more 
springs,  so  that  with  light  winds  one  only  is  compressed,  and  two,  or  more, 
according  to  the  strength  of  the  wind. 

The  pluviometer  is  placed  on  the  right  in  the  figure,  PP  being  the  plane  of 
the  roof  of  the  building.  The  rain  funnel,  R,  exposes  an  area  of  about  two 
hundred  square  inches.  The  water  collected  in  it  is  conveyed  by  a  tube  through 
the  roof  of  the  building  into  a  glass  vessel,  (•?,  so  adjusted  and  graduated  as  to 
indicate  a  quarter  of  an  inch  of  rain  for  every  two  hundred  square  inches  of 
surface,  i.e.,  50  cubic  inches.  0  is  supported  by  spiral  springs,  b  b,  which  are 
compressed  by  the  accumulating  rain.  A  glass  tube,  open  at  both  ends,  is 
cemented  into  the  bottom  of  G,  and  over  it  is  placed  a  larger  one  closed  at  the 
top  like  a  bell  glass.  The  smaller  tube  thus  forms  the  long  leg  of  a  syphon, 
and  the  larger  tube  acts  as  the  short  leg.  The  water,  having  risen  to  the  level 
of  the  top  of  the  inner  tube,  drops  over  into  a  little  copper  tilt,  t,  in  the  globe, 
S,  beneath  the  reservoir.  This  tilt  is  divided  into  two  equal  partitions,  and 
placed  upon  an  axis  not  exactly  balanced,  but  so  that  one  end  or  the  other  pre- 
ponderates. The  water  drops  into  the  end  of  the  tilt  which  happens  to  be 
uppermost,  and  when  quite  full  it  falls  over,  throwing  the  water  into  the  globe, 
S,  from  which  it  flows  away  by  the  waste  pipe.  In  this  way  an  imperfect 
vacuum  is  produced  in  the  globe,  quite  sufficient  to  produce  a  draught  in  the 

45,  COBNHILL,  E.G.,  AND  122,  BEGENT  STREET,  W.,  LONDON.       109 

small  tube  of  the  syphon,  or  the  long  leg  ;  and  the  whole  contents  of  the  reser- 
voir, 6r,  immediately  run  off,  and  the  spiral  springs  6  &,  elevate  the  reservoir  to 
its  original  position.  To  produce  this  action,  a  quarter  of  an  inch  of  rain  must 
have  fallen.  The  registration  is  easily  understood.  A  spring  lever,  z,  carrying 
a  pencil,  is  attached  by  a  cord,  c,  to  S.  This  spring  always  keeps  the  cord 
tight,  so  that  as  the  apparatus  descends  during  the  fall  of  rain,  the  spring 
advances  the  pencil  more  and  more  from  the  zero  of  the  scale  upon  the  paper 
beneath,  until  a  quarter  of  an  inch  has  fallen,  when  the  pencil  is  drawn  back  to 
zero  by  the  ascent  of  the  reservoir. 

The  registration  trace  for  twenty-four  hours  is  readily  understood.  The 
direction  is  recorded  on  the  centre  part ;  the  pressure  on  one  side,  and  the  rain 
on  the  other.  Lines  parallel  to  the  length  of  the  paper  show  no  rain,  steady 
wind,  and  constant  pressure.  On  the  rain-trace,  a  line  parallel  to  the  width  of 
the  paper,  shows  that  the  pencil  had  been  drawn  back  to  zero,  a  quarter  of  an 
inch  of  rain  having  fallen.  The  hour  lines  are  in  the  direction  of  the  width  of 
the  paper. 
Price,  for  Osier's  Self-registering  Anemometer  and  Rain  Gauge,  fig.  117,  from  £84  to  £150. 

150.  Beckley's  Anemometer. — Mr.  R.  Beckley,  of  the  Kew  Observatory, 
has  devised  a  self-registering  anemometer,  which  consists  of  three  principal 
parts :  Robinson's  cups  for  the  determination  of  velocity ;  a  double  fan,  or 
windmill  governor,  for  obtaining  the  direction  ;  and  a  clock  to  move  a  cylinder, 
around  which  registration  paper  is  wrapped.  The  paper  records  the  time, 
velocity,  and  direction  of  the  wind  for  twenty-four  hours,  when  it  must  be 
replaced.  It  has  a  cast-iron  tubular  support,  or  pedestal,  to  carry  the  external 
parts — the  cups  and  the  fan, — which  must  be  erected  upon  the  roof  of  the 
building  upon  which  it  is  desired  to  mount  the  instrument. 

The  fans  keep  their  axis  at  right  angles  to  the  wind ;  and  with  any  change 
of  direction  they  move,  carrying  with  them  an  outer  brass  tube,  which  rests 
upon  friction  balls  on  the  top  of  the  pedestal,  and  is  attached  to  a  tubular  shaft 
passing  through  the  interior  of  the  pedestal,  and  terminating  with  a  mitre 
wheel.  The  mitre  wheel,  working  with  other  cogged  wheels,  communicates 
the  motion  of  the  direction  shaft  to  a  cylinder  carrying  a  pencil,  to  record  the 

The  shaft  carrying  the  cups  is  supported  upon  friction  balls,  placed  in  a 
groove  formed  on  the  top  of  the  direction  shaft,  and  passing  through  the 
interior  of  that  shaft,  comes  out  below  the  mitre  wheel,  where  it  is  terminated 
in  an  endless  screw,  or  worm. 



Beckley's    Recording    Anemometer. 

Upon  the  wind  moving  the  cups  motion  is  given  to  the  innermost  shaft, 
thence  to  the  wormwheel,  whence  motion  is  given  to  a  pencil  which  registers 
the  velocity. 

45,    COKNHILL,    E.G.,    AND    122,    KEGENT    STREET,   W.,    LONDON.  Ill 

De  La  Rue's  metallic  paper  is  used  in  registration,  it  having  the  property 
of  receiving  a  trace  from  a  brass  pencil;  The  pencils  can,  therefore,  be  made 
in  the  most  convenient  form.  Mr.  Beckley  forms  each  pencil  of  a  strip  of 
brass  wrapped  round  a  cylinder,  making  a  very  thin  threaded  screw,  so  that 
the  contact  of  the  pencil  cylinder  and  the  clock  cylinder  is  a  mere  point  of  the 
metallic  thread.  The  pencil  cylinders  are  placed  side  by  side  upon  the  drum 
turned  by  the  clock,  and  require  no  spring  or  other  appliance  to  keep  them  to 
their  work,  but  always  make  contact  with  the  registration  paper  by  their  own 
gravity.  They  therefore  require  no  attention,  and  being  as  long  as  the  trace 
which  they  make  they  will  last  a  considerable  time. 

The  velocity  pencil  has  only  one  turn  on  the  cylinder,  and  its  pitch  is  equal 
to  a  scale  of  fifty  miles  upon  the  paper.  The  direction  pencil  has  likewise  one 
turn  on  its  cylinder,  its  pitch  being  equal  to  a  scale  of  the  cardinal  points  of 
the  compass  upon  the  paper.  The  Clock  gives  a  uniform  motion  of  half  an 
inch  per  hour  to  the  Drum  upon  which  the  paper  is  secured. 

In  the  Report  of  the  British  Association  for  1858,  Mr.  Beckley  has  given  a 
detailed  description  of  his  Anemometer,  with  drawings  of  all  the  parts.  Our 
engravings  (figs.  118  and  118°)  show  the  general  arrangement  and  details. 

The  price  of  Beckley 's  Anemometer  depends  so  much  upon  the  fittings 
and  the  amount  of  work  required  to  suit  it  to  the  building  upon  which  it  is  to 
be  fixed  that  Negretti  and  Zambra  can  only  quote  £80  to  £120  as  the  probable 
cost  of  the  instrument. 

151.  Negretti  and  Zambra' s  Anemometer  as  erected  on  their  Holborn 
Viaduct  Establishment,  shewing  Direction  and  Pressure  on  Dials  in  the  base  of 
the  building.  Cost  according  to  position  in  which  it  is  to  be  fixed. 

Special  Estimates  given  for  numbers. 

152.  Our  List  of  Registering  Anemometers  will  hardly  be  deemed  complete  without  the 
mention  of  some  exceedingly  ingenious  contrivances  for  obtaining  records  of  the  movements 
of  the  wind  by  the  use  of  a  Galvanic  current  so  arranged  that  any  alteration  in  the  direction 
or  force  of  the  wind  is  instantly  carried  down  to  a  dial  or  revolving  drum  or  other  me- 
chanical contrivance  for  receiving  the  indications. 

A  very  elaborate  description  will  be  found  in  Kaemtz's  Meteorology,  of  Professor 
Wheatstone's  Electro-Magnetic  Meteorological  Register,  and  in  several  foreign 
meteorological  publications  will  also  be  found  details  of  many  similar  applications 
of  the  electric  current. 

Louis  J.  Crossley,  Esq.,  of  Halifax,  has  devoted  a  very  large  amount  of  time  and 
attention  in  perfecting  a  recording  modification  of  Kobinson's  Anemometer,  in  connection 
with  a  galvanic  receiving  and  transmitting  apparatus  with  considerable  success  ;  but  owing 
to  the  difficulty  of  maintaining  the  connections  and  contact  breaks  in  perfect  working  order, 
and  the  consequent  probability  of  defects  in  the  registration,  the  Electro-Magneto 
Anemometers  are  but  rarely  used. 

N.  and  Z.  have  recently  fitted  up  several  different  arrangements  of  Electrical 
Anemometers  to  special  order  and  drawings,  these  under  careful  supervision  are 
now  performing  satisfactorily. 



153.  Ozone*. — During  the  action  of  a  powerful  electric  machine,  and  in 
the  decomposition  of  water  by  the  voltaic  battery,  a  peculiar  odour  is  perceptible, 
which  is  considered  to  arise  from  the  generation  of  a  substance  to  which  the 
term  Ozone  has  been  given,  on  account  of  its  having  been  first  detected  by  smell, 
which  for  a,  long  time  after  its  discovery  was  its  only  known  characteristic.  A 
similar  odour  is  evolved  by  the  influence  of  phosphorous  on  moist  air,  and  in 
other  cases  of  slow  combustion.  It  is  also  traceable,  by  the  smell,  in  air, — 
where  a.  flash  of  lightning  has  passed  immediately  before. 

Ozone  according  to  Faraday  is  oxygen  is  an  allotropic  condition,  and  from 
the  observations  of  Mr.  Glaisher  is  to  be  found  almost  always  present  in  the 
atmosphere ;  the  quantity  depending  on  the  elevation  above  the  surface  of  the 
earth,  and  the  prevalence  of  particular  winds,  being  more  abundant  during 
southerly  than  during  northerly  winds,  and  at  a  high  elevation  than  at  the 
surface  of  the  earth.  It  is  more  abundant  at  the  sea-side  than  inland,  and  is 
almost  absent  in  thickly-populated  towns.  This  may  seem,  remarks  Admiral 
FitzRoy,  in  The  Weather  Book,  to  point  to  some  connection  between  Ozone  and 
Chlorine  gas,  which  is  present  in  and  over  sea  water,  and  is  no  doubt  brought 
inland  by  any  wind  blowing  from  the.  sea. 

Ozone  plays  an  important  part  in  the  purification  of  the  atmosphere,  and 
its  continued  presence  in  a  locality  indicates  a  pure  and  healthy  climate.  More 
and  careful  observations  are  however  required  before  its  true  functions  can  be 

M.  Howzeau  states  :  That  the  amount  of  Ozone  in  the  air  is  variable,  the 
maximum  being  about  one  volume  of  Ozone  in  700,000  of  air.  Ozone  possesses 
the  property  of  bleaching  blue  litmus  paper  without  previously  reddening  it, 
and  it  is  found  present  most  in  Spring,  less  in  Summer,  diminishing  in  quantity 
in  Autumn,  and  very  little  in  Winter.  Generally  it  may  be  detected  during 
Wet  and  Stormy  weather,  and  largely  augmented  in  quantity  after  heavy  Snow 

Dr.  B.  W.  Richardson,  F.R.S.,  in  a  Lecture  on  Yital  Air,  delivered  at 
the  Society  of  Arts,  states,  as  an  undoubted  fact,  that  he  found  that  oxygen 
which  had  been  rendered  prejudicial  to  animal  life  from  repeated  breathing  was 
restored  by  means  of  an  electric  discharge  to  its  original  exhilarating  state, 
and  was  again  capable  of  supporting  animal  life.  So  that  there  is,  possibly,  a 
very  close  relation  between  the  electrical  condition  of  the  atmosphere  and  the 
amount  of  ozone  present,  as  indicated  by  the  Ozonometer.  The  ozone  is  usually 

*  Discovered  by  Schonbein  in  1848. 

45,    CORNHILL,    B.C.,    AND    122,    REGENT    STREET,    W.,    LONDON.  113 

in  excess  during  disturbed  electrical  weather,  and  in  a  deficiency  during  calm 
and  settled  periods.  We  cannot  lay  too  great  a  stress  on  the  fact  that  where 
different  kinds  of  ozone  tests  are  made  use  of  by  different  observers,  no 
uniformity  in  results  can  be  attained.  Having  this  in  view,  we  have  prepared 
our  ozone  tests  (see  No.  157)  on  a  formula,  by  which  we  can  obtain  uniformity 
in  the  indication  and  results  that  can  be  compared  no  matter  how  far  the 
stations  may  be  removed  from  one  another.  It  is  important  to  note  this,  as  we 
often  receive  complaint  of  the  failure  of  other  Ozone  Test  Papers.  It  is  recom- 
mended to  take  observations  every  twelve  hours  where  practicable,  as  there  is 
a  marked  difference  in  the  amount  of  ozone  registered  in  the  day  and  night. 


A  simple  method  of  producing  Ozone  is  passing  sparks  from  an  Electrical 
Machine  through  a  confined  portion  of  Air  in  a  glass  vessel. 

154.  Ozone  Tube. — A  convenient  form  of  apparatus  for  the  production  of 
Ozone.     It  consists  of  a  glass  tube  about  j  of  an  inch  diameter,  and  five  or  six 
inches  in  length,  coated  outside  with  tinfoil  and  enclosed  in  an  outer  tube,  also 
covered  outside  with  tinfoil.     These  tubes  are  so  arranged  that  the  intervening 
space  between  the  tubes  shall    be  as  small  as  possible;    the  coating  of  the 
inner  tube  being  put  into  connection  with  the  terminal  of  the  secondary  coil  of 
an   inductorium,  and  the  outer  coating  connected  with  the  other  terminal  of  the 
same  coil.     The  apparatus  forms,  in   fact,  a  kind   of  Leyden  Jar,  and  air   or 
oxygen  passing  between  the  tubes  when  the  coil  is  in  action  becomes  very 
strongly  ozonised.     The  air  to  be  operated  on  is   either  to  be  drawn  or  forced 
through  the  apparatus  by  the  aid  and  use  of  an  Aspirator  or  Gasometer. 

Price  for  the  above,  conveniently  mounted          .        .        .£150 

155.  Ozone  may  also  be  made  by  passing  a  current  of  dry  air  or  oxygen 
from  a  gasometer  through   a  narrow  glass  tube,  bent  for  convenience  like  the 
letter  U,  about  three  feet  in  length,  and  containing  a  platinum  wire  two  feet  in 
length,  inserted  into  the  interior  of  the  tube,  and  one  end  of  which  communi- 
cated with  the  outside  through  the  wall  of  the  tube.     Round  the  whole  external 
surface  of  this  U-shaped  tube  a  spiral  of  copper  wire  is  to  be  coiled,  and  an 
induction  current  (from  a  coil  giving  half-inch  sparks),  is  to  be  passed  between 
the  external  copper  to  the  internal  platinum  wire,  so  as  to  have  the  platinum 
wire  as  the  negative  pole  in  the  interior  of  the   glass  tube.     After  a  stream 
of  gas  is  ozonised  by  the  transmission  of  the  induction-current,  it  is  to  be 
washed  by  passing  it  through  a  bulb  tube  containing  caustic  potash,  when  air 
is  employed ;  or  water,  when  pure  oxygen  is  used ;  in  order  to  eliminate  any 
traces  of  nitrous  and  nitric  acids   that  may  have  been  formed.     By  means  of 
a  gasometer  the  volume  of  gas  passing    through  the   tube    may   be   exactly 



The  apparatus  described  afc  No.  155  was  used  by  Mr.  Dewar  and  Dr. 
McKendrick  in  carrying  out  some  experimental  research  on  the  Physiological 
Action  of  Ozone,  the  results  being  communicated  by  them  to  the  Royal  Society 
of  Edinburgh.  In  their  paper  the  authors  point  out  that  little  was  known 
regarding  the  action  of  Ozone,  except  its  peculiar  smell  and  the  irritating  effect 
it  had  on  the  mucous  membrane  of  the  respiratory  tract.  Schonbein  had  shown 
that  a  mouse  died  in  five  minutes  in  an  atmosphere  highly  charged  with  Ozone  ; 
and  it  was  this  distinguished  investigator  who  asserted  that  there  was  a  relation 
between  the  quantity  of  Ozone  in  the  air  and  the  prevalence  of  epidemic  diseases. 

The  result  of  Messrs.  Dewar  and  McKendrick's  experiment  was,  that  a 
full  grown,  healthy  mouse  lived  nineteen  minutes  after  the  introduction  of 
ozone  into  the  confining  vessel,  and  that  in  ozonised  oxygen,  instead  of  dying 
at  the  end  of  fifteen  or  twenty  minutes,  (as  happened  to  mice  in  ozonised  air), 
they  lived  for  forty  or  sixty  minutes. 

In  concluding  the  paper  the  authors  stated  that  it  would  be  premature,  at 
this  stage  of  the  inquiry  (which  opened  up  many  points  of  interest  in  the 
physiology  of  respiration),  to  generalise  between  physiological  action  and  the 
physical  and  chemical  properties  of  ozone.  Series  of  researches  are  still  being 
prosecuted  («)  on  the  action  of  smaller  percentages  of  ozone  ;  (&)  on  the  action 
of  ozone  on  noxious  gases  and  effluvia  ;  and  (c)  on  any  therapeutical  or  hygienic 
influences  it  may  have  on  the  origin  and  treatment  of  zymotic  diseases. 

156.  Dr.  Moffatt's  Ozonometer  consists  of  strips  of  paper  prepared  with 
Iodide  of  Potassium  and  Starch  ;  these  papers  are  suspended  in  a  box  so  as  to  be 
exposed  to  the  free  access  of  air,  protected  from  the  direct  rays  of  the  sun  and  also 
from  rain.     The  paper  when  affected  by  Ozone  is  tinged  with  various  shades 
of  brown,  the   intensity   of  which  is  measured   by  a  scale  of  ten  gradations 
furnished  with  the  test  papers. 

157.  Negretti  and  Zambra's  Ozonometer.  These  tests  are  now  prepared 
on  a  nevv  formula,  by  which  uniformity  in  the  indications  is   secured  together 
with  great  sensitiveness  and  keeping  qualities. 

In  Tin  Boxes  sufficient  for  12  months'  observations,  with  Colour  scale  and 

full  instructions  for  use Price,  8s.  6d. 

158.  Schonbein's  Ozone  Tests  Price,    6s.  6d. 

159.  Ozone  Box,  constructed  of  painted  deal  on  the  plan  recommended  by 
Dr.  Moffatt.  Price,     £110 

160.  Sir  James  Clarke's  Ozone  Case  (fig.  119),  consists  of  two  cylinders 
of  very  fine  wire  gauze,  one  fitting  into  the  other ;  the  wire  gauze  being  of  such 
a  fineness  as  to  permit  the  free  ingress  of  air,  at  the  same  time  that  it  shuts  out 
all  light  that  would  act  injuriously  on  the  test  paper,  which  is  suspended  by  a 
clip  or  hook  attached  to  the  upper  part  of  the  inner  cylinder.        Price,   £0  18    0 

Ditto  in  Copper  £150 

161.  Lowe's  Ozone  Case,  Spiral  form,  japanned  zinc.       Price,    £0  18    6 

45,    COEJfHILL,    E.G.,   AND    122,    REGENT    STREET,    W.,    LONDON,  115 

FIG.  119. 

FIG.  120. 

162.  Atmospheric  Electricity. — The  general  electrical  condition  of  the 
atmosphere  is  positive  in  relation  to  the  surface  of  the  earth  and  ocean,  becoming 
more  and  more  positive  as  the  altitude  increases.  When  the  sky  is  overcast, 
and  the  clouds  are  moving  in  different  directions,  it  is  subject  to  great  and 
sudden  variations,  changing  rapidly  from  positive  to  negative,  and  the  reverse. 
During  fog,  rain,  hail,  sleet,  snow,  and  thunderstorm,  the  electrical  state  of  the 
air  undergoes  many  variations.  The  intensity  of  the  electricity  increases  with 
hot  weather  following  a  series  of  wet  days,  or  of  wet  weather  coming  after  a 
continuance  of  dry  days.  The  atmospheric  electricity,  in  fact,  seems  to  depend 
for  its  intensity  and  kind  upon  the  direction  and  character  of  the  prevailing 
wind,  under  ordinary  circumstances.  It  has  an  annual  and  a  diurnal  variation. 
There  is  a  greater  diurnal  change  of  tension  in  winter  than  in  summer.  By 
comparing  observations  from  month  to  month,  a  gradual  increase  of  tension 
is  perceived  from  July  to  February,  and  a  decrease  from  February  to  July. 
The  intensity  seems  to  vary  with  the  temperature.  The  diurnal  variation 
exhibits  two  periods  of  greatest  and  two  of  least  intensity.  In  summer,  the 
maxima  occur  about  10  a.m.  and  10  p.m. ;  the  minima  about  2  a.m.  and  noon. 
In  winter,  the  maxima  take  place  near  10  a.m.  and  8  p.m. ;  the  minima  near 
4  a.m.  and  4  p.m. 




FIG.  121.  FIG.  122.  FIG.  123.  FIG.  124. 

163.  Singer's    Electrometer     for     Atmospherical     Electricity. 

(fig.  120). — This  instrument  is  arranged  with  a  brass  rod  about  two  feet  in  length 
and  a  clip  for  the  reception  of  a  lighted  cigar  fusee  ;  the  electricity  is  collected 
by  the  flame,  and  cond acted  down  the  rod  to  a  pair  of  gold  leaves,  which 
separate  according  to  the  amount ;  the  kind  is  determined  by  the  effect  of 
either  a  stick  of  excited  sealing-wax,  or  a  glass  rod,  supplied  with  the  instrument 

A  glass  rod  when  rubbed  produces  positive  electricity  ;  a  stick  of  sealing- 
wax  similarly  treated  produces  negative  ;  if,  therefore,  when  the  leaves  are  sepa- 
rate, we  apply  an  excited  glass  rod,  and  they  separate  still  further,  the  electricity 
is  positive ;  if  they  approach  it  is  negative  ;  on  the  contrary,  if  we  use  a  stick  of 
sealing-wax,  the  leaves  will  separate  if  they  are  charged  with  negative  electricity, 
and  converge  if  positively  charged,  from  the  fact  that  all  bodies  similarly 
electrified  repel  each  other,  whilst  those  oppositely  electrified  attract  each  other. 


A  book  containing  strips  of  gold  leaf,  to  replace  the  gold  leaves  when  torn 
or  broken  in  use.  Price  £016 

To  mount  fresh  gold  leaves,  unscrew  and  withdraw  the  brass  plate  to 
which  is  attached  the  rod  supporting  the  leaves  :  then  moisten  with  the  breath 
the  flat  piece  of  brass,  and  press  it  gently  down  on  one  strip  of  gold,  whilst 
the  book  is  only  partly  opened  ;  the  second  leaf  is  attached  in  the  same  manner. 

164.  Bohnenberger's  Electroscope  (fig.  121),   with   Zamboni's   Dry 
Piles,  arranged  with  adjustments  for  regulating  the  distance  between  the  gold 
leaf  and  the  polar  plates,  an  exceedingly  delicate  instrument  for  indicating  the 
presence  and  quality  of  electrical  currents. 

It  can  be  mounted  with  a  metallic  conductor,  and  used  with  great  advan- 
tage for  observing  atmospheric  electricity.  The  principal  parts  of  the  instrument, 
as  improved  by  Becquerel,  are  the  following:—^  I?,  fig.  96,  is  a  small 

45,    CORNHILL,    EC,    AND    122,    BEGEtfT    STREET,    W.,    LONDON.  117 

Zamboni's  dry  galvanic  pile  of  800  pairs,  about  a  quarter  of  inch,  in  diameter  ; 
and  when  the  plates  are  pressed  together,  2 \  inches  in  length.  The  bent  wires 
above  the  pile  terminate  in  two  plates,  P  and  If,  which  are  the  poles  of  the 
pile.  These  plates  are  parallel  and  opposite  to  each  other.  Their  opposite 
sides  are  slightly  convex,  and  gilded  ;  between  is  suspended  a  fine  gold  leaf,  ~D 
G,  which  is  attached  to  the  metal  conductor,  C  D.  If  the  leaf  hang 
exactly  between  the  two  plates,  it  is  equally  attracted  by  each,  and  will  be  in  a 
state  of  repose.  The  apparatus  is  protected  by  a  glass  shade,  having  an  opening 
at  the  top  through  which  the  metal  wire,  C  D,  passes,  insulated  by  being  con- 
tained in  a  glass  tube,  which  is  cemented  to  the  glass  shade  by  means  of  shellac. 
A  metal  plate  is  attached  to  the  wire  rod  in  connection  with  the  gold  leaf  to 
convey  to  it  the  electricity  to  be  tested.  The  electricity  to  be  tested  will  be 
conveyed  by  the  metal  wire  to  the  gold  leaf,  and  the  latter  will  immediately 
move  towards  the  plate  which  has  the  opposite  polarity.  This  electroscope  is, 
beyond  doubt,  one  of  the  most  delicate  ever  constructed,  and  is  well  adapted  to 
show  small  quantities  of  positive  and  negative  electricity.  Price,  £880 

165.  Volta's  Straw  Electrometer,  with  graduated  Arc,  for  estimating 
the  amount  of  electric  force  by  degrees  of  divergence.  Price,    £220 

166.  Cavallo's  Pith.  Ball  Electroscope,  (fig.  122)  with  graduated  Arc 
for  estimating  the  amount  of  electric  force  ....  Price,  £t  10    0 

167.  Ditto  ditto         with  Stopcock,  fig.  123    .         .220 

168.  Peltier's   Tension  Electrometer,*   (fig.   124)  according   to  Mr. 
Latimer  Clark,  was  in  all  its  essential  parts  first  described  and  illustrated  by 
Dr.  Thomas  Milner  in  the  year  1 733.     The  instrument  described  as  the  inven- 
tion of  Peltier  in  the  Report  of  the  British  Association,  1849,  and  termed  the 
Induction  Electrometer,  is  constructed  as  follows  : — 

It  consists  of  a  light  metal  ball  of  about  4J  inches  diameter  mounted  on 
a  brass  rod,  terminating  in  a  flattened  oval  or  heart-shaped  aperture.  In  the 
centre  of  this  aperture  is  placed  a  fine  steel  point  on  which  is  suspended  a  light 
copper  or  aluminium  wire  needle,  with  a  small  magnetic  needle  mounted  on  it 
at  right  angles.  Two  light  metal  rods  or  arms  are  extended  from  opposite 
sides  of  the  support  of  the  ball  of  the  same  length  as  the  copper  needle. 
Below  these  rods  is  a  graduated  circle,  for  estimating  the  value  of  the  deflection 
of  the  needle  in  degrees.  The  support  of  the  ball  and  centre  of  the  needle  is 
very  carefully  mounted  and  insulated  on  ebonite,  and  the  whole  mounted  on  a 
mahogany  base  with  three  adjusting  screws.  A  cylindrical  glass  cover  is 
placed  over  the  graduated  circle  and  indicating  needle  to  protect  them  from 
currents  of  air,  dust,  &c. 

In  use  this  electrometer  is  very  carefully  placed  in  such  a  position  that  the 
magnetic  needle  shall  cause  the  light  copper  wire  index  needle  to  lie  parallel 

*  Peltier's  Electrometer  as  used  by  Professor  Palmier!  at  the  Observatory  on  Mount  Vesuvius. 


with  and  almost  touching  the  two  brass  arms,  when,  if  the  apparatus  lias  been 
properly  adjusted,  if  any  cloud  or  portion  of  air  in  its  vicinity  be  in  an  electrical 
condition  it  will  act  by  induction  upon  the  metal  ball,  and  the  needle  will  be 
deflected  according  to  the  amount  and  tension  of  the  electricity. 

The  quality  of  the  electricity,  if  positive  or  negative,  may  be  ascertained  by 
the  use  of  a  rod  of  glass  or  shellac  as  described  in  directions  for  using  the  gold 
leaf  instrument.  (No.  163) 

In  atmospheric  observations  the  instrument  may  either  be  charged  with 
free  electricity  and  the  indications  of  this  needle  noted  at  certain  intervals,  or  it 
may  be  brought  to  the  same  degree  of  tension  as  the  earth,  and  the  inductive 
effects  of  the  atmosphere  upon  it  observed.  Owing  to  its  greater  convenience  the 
former  method  is  now  generally  adopted,  but  the  variations  of  the  needle  under 
atmospheric  influences  are  far  from  being  understood  or  reduced  to  a  system. 

In  use  the  Induction  Electrometer  is  placed  upon  a  stand  about  six  feet  from 
the  ground,  and  to  bring  it  into  equilibrium  of  tension  with  the  earth,  touch 
the  base  of  the  stem  with  a  conducting  wire.  When  the  instrument  is  removed 
from  the  inductive  influence  it  indicates  the  presence  of  free  electricity  by  the 
deflection  of  the  needle. 

A  regular  and  uninterrupted  series  of  atmospheric  observations  with  the 
Peltier  instrument  were  made  by  M.  Quetelet  at  the  Royal  Observatory  at 
Brussels  from  August,  1844,  till  December,  1848. 

A  strong  inductive  influence  was  generally  noticed  at  the  approach  or 
cessation  of  rain.  The  maximum  of  atmospheric  electricity  was  indicated  in 
January,  the  tension  of  the  atmospheric  charge  progressively  diminishing  until 
June,  when  it  attained  its  minimum.  The  difference  of  the  tension  in  these 
two  months  was  in  the  proportion  of  13  to  1.  The  results  obtained  by  Mr.  R. 
Birt  at  Kew  are  closely  in  accordance  with  those  of  M.  Quetelet. 

Peltier's  instrument  is  now  constructed  with  a  smaller  ball,  and  without 
the  metal  shade  as  shown  in  our  engraving,  and  the  whole  apparatus  carefully 
insulated  with  ebonite  (vulcanite),  in  place  of  shellac  and  resin.  Price,  £550 

169.  Thomson's  Quadrant   Electrometer    complete  with  Lamp  and 

Scales,  including  directions  for  use,  in  Mahogany  Case,  with  Lock  and  Key. 

£36    0    0 

170.  Professor      Sir     W.      Thomson's      Portable     Atmospheric 
Electrometer  (attracted   disc),   fully   described   in    Negretti   and    Zambra's 
Treatise  on  Meteorological  Instruments,  paragraph  135,  pp.  130  and  131. 

Price  with  Electrophorous  fitted  in  Mahogany  Box     £12     0    0 

171.  We  have  still  to  note  the  want  of  a  portable  and  simple,  but  at  the 
same  time,  accurate  instrument  to  denote  the  electrical  condition  of  the 
atmosphere.  Many  forms  of  Electrometers  lately  devised  are  but  of  little 
use  to  ordinary  observers  from  their  complex  construction. 

45,  COENHILL,  E.G.,  AND  122,  EEGENT  STEEET,  W.,  LONDON.       119 

172.  Collection  of  Electricity. — "A  simple  rough  method  of  doing  this 
is  to  shoot  a  metallic  arrow  upwards  into  the  air,  the  arrow  being  tied  to  one 
end  of  a  conducting  string,  the  lower  end  of  which  carries  a  ring  which  rests 
upou  the  electroscope.     The  arrow  being  shot  upwards,  the  electroscope  will  be 
found  to  be  electrified,  as  it  mounts  ;  and  when  the  ring  leaves  the  plate,  the 
instrument  will  indicate  the  state  of  electrification  of  the  air  at  that  point  where 
the  arrow  is  at  the  time. 

"This  manner  of  observing  is  simplified  by  substituting  a  long  conductor 
reaching  upwards;  a  gilded  fishing  rod  may  be  employed,  its  lower  extremity 
being  insulated. 

"  The  usual  method  employed,  however,  is  Volta's,  in  which  the  electricity 
is  collected  by  means  of  a  flame,  burning  at  a  height,  either  in  a  lantern  hung 
to  mast,  and  connected  to  the  electroscope  by  a  wire,  or,  by  a  slow  burning 
match  attached  to  the  top  of  a  long  metal  rod. 

"  The  electricity  of  the  air  in  the  neighbourhood  of  the  flame,  by  its  induc- 
tive action  upon  the  conductor,  causes  electricity  of  the  opposite  nature  to 
accumulate  at  the  upper  extremity,  where  it  is  constantly  carried  off  by  the 
convection  currents  in  the  flame,  leaving  the  conductor  charged  with  electricity 
of  the  same  kind  and  potential  as  the  air."* 

173.  "  The  princple  of  Volta's  method  has  been  made  use  of  by  Sir  W. 
Thomson  in  his  Water-dropping  Collector,  now  employed  in  observatories,  and 
found  to  be  extremely  useful  for  the  observation  of  atmospheric  electricity. 

A  copper  can  is  placed  on  an  insulating  support,  which  may  be  of  ebonite, 
having  the  surface  thinly  coated  with  paraffin ;  or  of  glass  surrounded  with  pumice 
stone  soaked  in  sulphuric  acid.  From  the  can  a  small  pipe  projects  a  consider- 
able distance  into  the  air,  and  terminates  in  a  fine  orifice.  The  can  being  filled 
with  water,  and  the  tap  which  opens  into  the  jet  pipe  turned  on,  a  small  stream 
of  water  is  allowed  to  flow  out,  care  being  taken  that  it  is  so  small  that  it  shall 
break  into  drops  immediately  after  leaving  the  nozzle  of  the  tube. 

In  half  a  minute  from  the  starting  of  the  stream  the  can  will  be  found  to 
be  electrified  to  the  same  potential  as  the  air  at  the  point  of  the  tube. 

This  Collector  cannot  be  employed  during  the  time  of  frost,  unless  means 
are  adopted  to  prevent  the  freezing  of  the  water  in  the  jet  pipe.  When  obser- 
vations are  to  be  made  with  a  portable  instrument,  a  slow  burning  match 
should  be  used.  Sir  William  Thomson  recommends  for  this  purpose  blotting 
paper,  steeped  in  a  solution  of  nitrate  of  lead,  dried,  and  rolled  into  matches. 

As  to  the  position  of  the  Collector,  since  electrical  density  is  greater  on 
projecting  surfaces,  and  less  on  hollow  surfaces  than  on  planes,  the  Collector 
should  not  be  near  trees  or  houses,  nor  within  a  closed  space."* 

The  above  Apparatus  and  Collecting  Match  made  to  order. 

*  Robert  H.  Scott,  Esq.,  Meteorological  Office. 


174.  Tide  Gauge,  Self-registering,  Wegretti  and  Zambra's  Im- 
proved Newman's  (fig.  125),  for  recording  the  rise  and  fall  of  the  tide,  by  a 
lined  traced  with  a  pencil  on  a  ruled  paper,  wound  on  a  cylinder  moved  round 
by  a  clock  once  in  twenty-four  hours.  The  paper  showing  the  rise  and  fall  in 
feet  and  inches,  and  also  the  time  in  hours.  An  exceedingly  valuable.instrument 
for  places  where  the  phenomena  of  tides,  and  the  construction  of  accurate  tide 
tables  are  of  the  utmost  importance.  Such  observations  should  also  be  accom- 
panied with  the  registration  of  atmospheric  phenomena. 

The  tide-gauge,  shown  in  the  illustration  (fig.  125)  consists  of  a  cylinder, 
A,  which  is  made  to  revolve  once  in  twenty-four  hours  by  the  action  of  the 
clock  B.  A  chain,  to  which  is  attached  the  float,  D,  passes  over  the  wheel,  (7, 
and  on  the  axis  of  this  wheel,  0  (in  about  the  middle  of  it),  is  a  small  toothed 
wheel,  placed  so  as  to  be  in  contact  with  a  large  toothed  wheel  carrying  a 
grooved  pulley,  E,  over  which  passes  a  small  chain.  This  chain,  passing  along 
the  upper  surface  of  the  cylinder,  A,  and  round  a  second  pulley,  F,  at  its 
further  end,  is  acted  on  by  a  spring  so  as  to  be  kept  in  a  constant  state  of 
tension.  In  the  middle  of  this  chain  a  small  tube  is  fixed  for  carrying  a  pencil, 
which,  being  gently  pressed  down  by  means  of  a  small  weight  on  the  top  of  it, 
marks  on  the  paper  placed  round  the  cylinder  the  progress  of  the  rise  or  fall  of 
the  tide  as  the  cylinder  revolves,  and  as  it  is  drawn  by  the  chain  forward  or 
backward  by  the  rise  or  fall  of  the  float.  The  paper  is  prepared  with  lines 
equi-distant  from  each  other,  to  correspond  with  the  hours  of  the  clock,  A, 
crossed  by  others  showing  the  number  of  feet  of  rise  and  fall. 

The  cylinder  while  in  action  revolves  from  left  to  right  to  a  spectator 
facing  the  clock,  and  the  pencil  is  carried  horizontally  along  the  top  of  this 
cylinder ;  the  large  wheel,  G,  is  caused  to  revolve  by  the  rise  and  fall  of  the 
float,  which  turns  the  wheel  with  the  small  pulley,  E,  attached  to  it.  If  the 
tide  is  falling,  the  small  chain  is  wound  round  the  cylinder,  E,  and  the  pencil  is 
drawn  towards  the  large  wheel ;  brst  if  the  tide  is  rising,  the  small  chain  is 
wound  on  the  cylinder,  F,  by  means  of  the  spring  contained  in  it.  Thus,  by 
means  of  the  rise  and  fall  of  the  tide,  a  lateral  progress  is  given  to  the  pencil, 
while  the  cylinder  is  made  to  revolve  on  its  axis  by  the  clock,  so  that  a  line  is 
traced  on  the  paper  showing  the  exact  state  of  the  tide  continuously,  without 
further  attention  than  is  necessary  to  change  the  paper  once  every  day,  and  to 
keep  the  pencil  carefully  pointed  ;  or  a  metallic  pencil  may  be  used.  As  indi- 
cated, it  is  self-recording,  requiring  very  little  attention — a  few  minutes  every 
day  being  sufficient. 

These  gauges  are  now  in  action  in  several  parts  of  the  world,  faithfully 
recording  the  rise  and  fall  of  the  tides. 

Price,  fig.  125,  N.  and  Z's.  Improved  arrangement,  from    £50    0    0 
NOTE.— The  price  for  the   Ruled  Papers  or   Charts  used  with  this  Apparatus   and 
No.  175,  along  with  Charts  for  other  Recording  Instruments,  will  be  found  on  page  132. 




A.  Dial  of  clock. 

B.  Float-wheel. 

C.  Guide    for      recording 


D.  Recording  pencil. 

E.  Hourly  marker  on 

datum  lines. 

F.  Datum    lines    and 

registering  pencil. 

G.  Main  Drum  driven  by 


H.     Eeel  of  paper. 
I.     Haul-off  drum. 
J.     Pendulum  of  clock. 
K.     Driving    weight    of 

L.     Driving    weight    of 

haul-off  drum. 
M.     Haul- off  drum  winder. 
K".     Platinum  wire  to  float. 

FIG.  126. 


175.  The  instrument  consists  of  an  astronomical  clock,  float- wheel  and 
gear  work  for  reducing  the  scale,  and  three  drums,  the  whole  fitted  on  a  suitable 
plate  and  supporting  standards,  and  requiring  no  further  fixing.  The  clock  is 
fitted  with  a  six- spur  gravity  escapement  and  compensated  pendulum,  and 
serves  to  show  the  time  and  to  drive  the  centre  or  main  drum  of  the  instru- 
ment. The  float  wheel  is  provided  with  a  right-angled  groove  in  which  the 
platinum  wire  of  the  float  coils  itself  during  the  rising  tide.  The  right-hand 
drum  receives  a  reel  of  paper,  and  the  paper  is  fitted  to  the  instrument  without 
further  fixing.  The  haul-off  drum  receives  the  paper  records  after  it  has 
passed  round  the  main  drum.  The  paper  may  be  left  to  accumulate  almost 
without  limit  on  the  haul-off  drum,  or  can  be  removed  at  any  time.  The 
datum  line  on  the  record  paper  is  traced  by  a  fixed  pencil,  which  can  be 
adjusted  to  any  level.  Any  number  of  horizontal  lines  can  be  ruled  in  this 
manner  if  desired. 

45,    COENHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  123 

Immediately  at  the  side  of  the  datum  line  registering  pencil,  is  a  pencil 
actuated  by  the  clock,  which  causes  it  to  trace  a  short  vertical  line  at  each 
hour,  through  the  datum  lines,  the  mark  for  noon  and  midnight  being  some- 
what different.  In  this  case  the  pencil  is  arrested  for  two  minutes  when  in 
marking  it  has  reached  the  level  of  the  datum  line,  when  it  is  allowed  to 
complete  the  marking.  The  distinction  is  introduced  in  order  to  facilitate  the 
subsequent  noting  of  the  times  and  dates  upon  the  record.  The  pencil  tide 
recorder  is  made  to  counterbalance  the  float. wire  when  the  scale  is  not  too 
greatly  reduced,  in  which  case  the  weight  of  the  float- wire  is  partially  relieved 
by  a  counterpoise  weight  acting  on  the  axis  of  the  float-wheel.  The  system  of 
making  the  recording  pencil  balance  the  float- wire  is  a  great  advantage  over  the 
system  generally  employed,  and  greater  accuracy  of  recording  is  secured.  The 
employment  of  a  continuous  roll  of  paper  obviates  the  necessity  of  continually 
applying  fresh  paper  to  the  recording  drum,  and  the  tide-gauge  can  thus  be  left 
untended,  except  for  the  purpose  of  winding  the  clock,  for  an  indefinite  period. 
The  system  also  of  ruling  the  paper  by  fixed  pencils  and  marking  the  hourly 
times  by  the  clock  constitutes  a  marked  improvement,  no  error  can  thus  occur 
from  the  wrong  setting  of  the  paper. 

Prices.    The  Tide-guage  with  three  barrels  and  continuous  paper  complete,  best  finish     £95 

Ditto  with  single  barrel  and  extra  finish     .         .        .        .fig.  126.     £80 

Ditto  ditto  to  be  used  with  previously  divided  paper    .     £54 

Larger  engravings  of  some  improvements  in   Thomson's  Tide  Gauge  sent 

upon  application. 

170.  Negretti  and  Zambra's  Portable  Set  of  Meteorological 
Instruments.  A  small,  but  at  the  same  time  really  useful  and  reliable  set  of 
Standard  Meteorological  Instruments  has  long  been  inquired  for  by  observers 
on  foreign  stations,  and  others  who  are  frequently  travelling  to  different  parts 
of  the  world.  To  meet  this  demand,  Messrs.  Negretti  and  Zambra  have 
arranged  sets  of  Meteorological  Instruments  to  pack  up  into  a  very  small  space. 
The  set  contains  ISTegretti  and  Zambra's  Patent  Maximum  and  Minimum 
Registering  Thermometers,  Wet  and  Dry  Bulb  Hygrometer,  Aneroid  Barometer 
for  Altitude  measurements,  Negretti  and  Zambra's  Improved  Registering 
Maximum  Thermometer  with  high  range  of  scale,  for  Hot  Springs,  Solar 
Radiation  Thermometer,  Terrestrial  Radiation  ditto,  Improved  Boiling  Point 
Apparatus,  Rain  Gauge  and  Graduated  Measure,  a  Clinometer,  Magnetic 
Compass,  and  Tape  Measure.  The  whole  arranged  in  a  strong  case;  with  lock 
and  key.  Price  £18  18  0 

These  sets  can  be  varied,  or  other  Instruments  added,  to  meet  the  wishes 
and  requirements  of  purchasers.  See  also  pages  106  and  107. 

Further  details  of  the  construction  and  use  of  Meteorological  Instruments  mil 
be  found  in  Negretti  and  Zambra's  TREATISE,  with  very  many  valuable  and  useful 
Tables  of  corrections,  fyc.,  fyc.  Seepage  133. 



177.     The  Meteorological  Congress  of  Vienna,  recognising  three  classes  of 
Observing  Stations,  we  subjoin  estimates  for  Sets  of  Meteorological  Instruments 
suited  to  their  requirements. 
No.  1. — For  an  Observatory  or  Station  of  the  First  Order. 

In  which  independent  meteorological  observations  are   conducted,   of    the    greatest 

precision,  either  by  hourly  readings  or  with  the  use  of  Self -Recording  Apparatus. 
One  Large  Observatory  Standard  Barometer. 
One  Independent  Standard  Thermometer. 

One  Negretti  and  Zambra's  Patent  Standard  Maximum  Registering  Thermometer. 
One  Negretti  and  Zambra's  Patent  Standard  Maximum  Thermometer, — 

Exposed  Black  Bulb. 
One        Ditto        Ditto        Bright  Bulb. 
One  Negretti   and  Zambra's   Improved   Patent  Maximum   Thermometer,  in  Vacuum, 

with  Test  Gauge,  No.  37.    With  Stand  for  ditto. 
One  Negretti  and  Zambra's  Standard  Minimum  Thermometer. 
One        Ditto  Ditto  Ditto  Mercurial. 

One        Ditto  Ditto  Standard  Terrestrial  Radiation  Thermometer. 

One  Standard  Wet  and  Dry  Bulb  Hygrometer. 
One  Stevenson's  Thermometer  and  Hygrometer  Screen. 
One  Glaisher's  Rain  Gauge,  the  New  Pattern,  complete,  Copper. 
Two  Extra  Graduated  Measures  for  above. 

A  Series  of  Thermometers  for  Earth  Temperatures  at  varying  depths. 
One  Negretti  and  Zambra's  Maximum  Thermometer,  for  Earth  or  Springs. 
One  Gold  Leaf  Electrometer. 
One  Anemometer,  with  two  recording  Dials. 
Recording  Mercurial  Barometer. 
Recording  Thermograph. 
Recording  Hygrometer. 
Recording  Anemometer  and  Rain  Gauge. 
Sunshine  Recorder. 

Cost  for  the  whole  of  above  Kew  verified,  £330  to  £450. 

In  first  class  Observatories  it  is  advisable  to  have  duplicate  instruments, 
where  there  is  any  liability  of  fracture,  to  avoid  breaking  off  the  continuity  of 
the  recorded  observations. 

The  No.  1  Set  of  Meteorological  Apparatus  can  be  much  extended  if  it  be 
desired,  to  make  comparative  or  experimental  observations. 
No.  2. — Estimate  for  a  Meteorological  Observatory  of  the  Second  Order. 
One  Standard  Barometer. 

One  Negretti  and  Zambra's  Patent  Standard  Maximum  Thermometer. 
One        Ditto        Ditto         Standard  Minimum  Thermometer. 
One  Solar  Radiation   Thermometer  in  Vacuo,   with  Negretti  and   Zambra's 
Improved  Test  Gauge. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  125 

One  Solar  Eadiation  Thermometer,  with  Exposed  Bulb. 

One  Terrestrial  Radiation  Thermometer. 

One  Glaisher's  Eain  Gauge,  Copper,  complete. 

One  Anemometer,  with  two  dials. 

One  Wet  and  Dry  Bulb  Hygrometer. 

One  Stevenson's  Thermometer  md  Hygrometer  Stand. 

Cost  for  the  above  Set  of  Apparatus,  £22  to  £25. 

No  2  Set  of  Apparatus  is  strongly  recommended  to  private  observers 
where  complete  and  regular  observations  are  taken  of  Barometric  Pressure, 
Temperature,  Humidity,  Rain,  Wind,  and  Electrical  phenomena. 

The  series  can  be  reduced  to  form  a  Third  Class  set  at  £12  12s.,  where 
only  a  few  of  the  more  important  meteorological  observations  are  taken,  or 
other  instruments  can  be  added  to  meet  the  requirements  of  the  observer. 

It  will  be  as  well  to  note  here  that  all  observations  should  be  made 
punctually  at  fixed  hours.  The  Meteorological  Office  recommend  that,  at 
Observing  Stations  of  the  second  order,  observations  be  made  at  least  twice  a 
day,  at  homonymous  *  hours,  for  which  9  a.m.  and  9  p.m.  (local  time),  have 
been  most  generally  approved  of.  In  unsettled  weather  occasional  observations 
should  be  made  of  any  special  meteorological  facts  that  may  occur. 


178.  The  Kew  Committee  of  the  Royal  Society  undertaking  the  testing 
and  verification  of  Meteorological  Instruments  by  their  Standards,  Negretti  and 
Zambra  subjoin  a  list  of  the  charges.  At  the  same  time,  Negretti  and  Zambra 
would  observe  that,  having  absolute  Standard  Instruments  of  their  own 
manufacture  which  have  been  compared  both  with  Greenwich  and  Kew 
Observatory  Standards,  they  are  prepared  to  compare  and  give  certificates 
with  their  own  instruments  free  of  charge, 

The  Kew  Committee  wish  it  to  be  noted  that  they  do  not  undertake  the 
verification  of  inferior  instruments,  such  as  Barometers  mounted  on  Wood 
Frames,  and  Thermometers  not  graduated  on  the  Stem,  and  also  that  the 
Superintendent  may  at  his  discretion  decline  to  receive  instruments  he  may 
consider  unfit  for  Scientific  observation. 


Standard  Barometers  with  attached  Thermometer 10s.  6d. 

Marine  Barometers  in  Metal  Mountings 15s.  Od. 

Aneroid  Barometers  for  Altitude  Measurements  compensated         .        .         15s.  Od. 

Thermometers 2s.  6d.  to  5s.  Od. 

Eain  Gauges 2s.  6d. 

*  The  term  "  homonymous  "  signifies  hours  of  the  same  name,  as  9  and  9,  or  12  and  12.    The  most 
suitable  hours  are,  to  a  certain  extent,  to  be  determined  by  the  locality  and  climate. 



N.  &  Z's  Maximum  Registering  Thermometer. 

&  Z's.  Minimum  Registering  Thermometer. 

N.  &  Z's.  Glashier's  Standard  Rain  Gauge. 

FIG.   127. 

179.      NEGRETTI   AND   ZAMBRA'S   FIVE    GUINEA    SET    OF 

consists  of  a  Mercurial  Barometer  with  attached  Thermometer  having 
Fahrenheit  and  Centigrade  Scales,  Registering  Maximum  Thermometer, 
Registering  Minimum  Thermometer,  Rain  Gauge  and  Graduated  Measure,  and 
a  Wet  and  Dry  Bulb  Hygrometer,  fig.  127. 

The  whole  of  these  instruments  are  very  carefully  manufactured  and  tested 
to  ensure  sufficient  accuracy  for  ordinary  observers  at  a  moderate  price.  One 
important  feature  in  this  set  is  that  the  various  instruments  will  travel  securely,  as, 
although  they  are  not  strictly  a  standard  set,  they  have  all  Negretti  and  Zambra's 
improvements  and  Patents  adapted  to  them,  and  are  compared  and  verified  by 
Negretti  and  Zambra,  and,  if  desired,  Certificates  given. 

This  set  of  meteorological  instruments  can  be  modified,  and  extended,  to  meet 
the  wishes  of  our  customers.  Descriptive  particulars  of  the  construction  and 
use  of  these  instruments  will  be  found  in  the  previous  pages,  or  in  Negretti  and 
Zambra's  Treatise  on  Meteorological  Instruments.  See  page  133. 

45,  CORNHILL,  E.G.,  AND  122,  REQENT  STREET,  W.,  LONDON. 



180.  Lightning  Conductors  should  be  pointed  at 
the  top,  and  extend  a  few  feet  above  the  highest  point  of 
the  building  or  mast.  They  are  best  made  of  Solid 
Copper  Hods  or  Copper  Bands  of  sufficient  diameter 
and  thickness  to  convey  the  discharge  without  melting. 
Wire  Hope  of  Copper  is  now  much  used,  owing  to  its 
convenient  adaptability  to  uneven  surfaces,  but  great 
care  must  be  taken  to  have  it  of  sufficient  diameter  to 
prevent  fusion,  and  that  both  solid  rods  and  wire  rope 
should  be  perfectly  continuous  and  unbroken  throughout 
the  entire  length,  and  carried  down  some  considerable 
distance  into  the  earth,  which  should  be  moist,  or  better 
still,  carried  down  a  well  some  distance  beneath  the 
surface  of  the  water,  or  the  conductor  should  terminate 
in  several  branches  on  a  large  sheet  of  stout  copper. 
In  large  towns  these  conductors  are  carried  down  and 
connected  with  the  large  water  pipes.  On  no  account 
should  Lightning  Conductors  be  connected  with  Gas 
pipes;  it  is  exceedingly  dangerous.  Where  a  building  is 
large,  several  conductors  should  be  used,  and  all  large 
and  detached  masses  of  metal  in  the  fabric  connected  together  and  then  united 
with  capacious  conductors  leading  directly  from  the  highest  points  of  the 
structure  to  the  earth  or  sea.  In  applying  such  conductors  to  ships,  each 
mast  should  have  its  own  conductor,  of  sufficient  size,  permanently  fixed,  and 
connected  with  bands  of  stout  copper  passing  through  the  sides  of  the  ship 
under  the  deck  beams,  and  with  the  large  bolts  leading  through  the  keels  and 
keelson  to  the  water,  including  in  the  circuit  all  the  principal  masses  of  metal 
used  in  the  construction  of  the  vessel. 

It  is  of  the  utmost  importance,  that  Lightning  Conductors  be  periodically 
examined  to  see  that  they  are  in  perfect  condition,  as  any  defects  in  continuity  of 
the  metal  rod  or  wire  may  lead  to  serious  results.  Several  instances  of  most 
destructive  damage  both  to  buildings  and  ships  having  lately  occurred,  arising 
from  defective  conductors,  we  cannot  too  strongly  urge  the  attention  to  this  caution. 

FIG.  128. 


FIG.  131. 

.   Solid  Copper  Point  Lightning  Conductor  with 
3  3  Attractors,  as  fig.  129,  Copper  elevating  tube 

25  5    feet  long,  Couplings,   Straining   Bolt,  Insu- 

lators, and  Holdfasts,  all  complete  with  50  feet 
Solid  Copper  Rope  f  inch  diameter  .         .         .     4  10     6 
Ditto         Ditto,    with    75  feet    Solid   Copper    Rope 

-|  inch  diameter  .          .          .          .         .  5  15     0 

Ditto         Ditto,  with  100  feet   Solid  Copper  Rope 

£  inch  diameter 700 

Ditto         Ditto,  with  150  feet  Solid  Copper    Rope 

£  inch  diameter          .         .         .         .         .         .     9  12     0 

Ditto         Ditto,   with   50    feet   Solid   Copper   Rope 

|  inch  diameter .         .          .         ...         .         .550 

Ditto         Ditto,  with  75    feet    Solid    Copper    Rope 

•|  inch  diameter  .         .         .         .         .         .  6  16     0 

Ditto         Ditto,   with  100   feet    Solid    Copper 

Rope  \  inch  diameter         .         .         .          .876 

Ditto         Ditto,  with  150   feet   Solid    Copper 

Rope  \  inch  diameter        .         .          .         .  11  10     0 

Ditto         Ditto,   with   100    feet    Solid   Copper 

Rope  J-  inch  diameter         .         .         .         .     9  16     0 

Ditto         Ditto,    with    150  feet   Solid   Copper 

Rope  f  inch  diameter        .         .         .         .  13  17     6 

Plain  Point  Solid  Copper  Bod  Lightning 
Conductor,  for  Copper  Rope  T^-  inch 
diameter,  no  Insulators  or  Tightening 
Bolt  (fig.  130) 150 

Plain  Spear  Point  Solid  Copper 
Lightning  Conductor  with  Coupling 
for  Rope  End  and  Copper  Elevating  Tube 
4  feet  long  (fig.  130*)  .  .  .  .  1  12  0 

FIG.  130* 

45,    COENHILL,    B.C.,    AND    122,    EEGENT    STREET,    W.,    LONDON. 

Solid  Copper  Lightning  Conductor  fitted  with  Point  and 
three  Attractors,  as  fig.  129,  with  7  Holdfasts,  7  Insulators,  and 
1  Straining  Bolt,  complete  ....... 

Ditto         Ditto,  with  11  Holdfasts  and  11  Insulators     . 

Ditto         Ditto,  with  15  Holdfasts  15  Insulators     . 

Ditto         Ditto,  with  24  Holdfasts  and   12  Insulators     . 


£      s. 

2  14 

3  0 

3  6 

4  4 

If  the  Points  are  wished  tipped  with  Platinum,  there  will  be  an  extra 
charge,  according  to  the  size  and  weight.  Price  variable. 

Galvanised  Iron  Holdfast,  to  build  in, 
Ditto  Ditto 

Ditto  Ditto 

Ditto  Ditto 

Straining  Bolt 

No.  1,  fig.  131,  per  doz. 
to  Drive  No.  4       Do.     per  doz. 

for  passing  along  Slated  Roof, 

No.  3     Do.      per  doz. 
extra  strong,  for  supporting  Bod  or 
.     No.  2     Do.      per  doz, 
Copper  Elevating  Rod,  No.   6,  fig.  130*,  showing  Holdfast  and 
Glass  Insulator,  to  steady  the  same    ...... 

Straining  Bolt,  No.  7,  fig.  130*,  with  Glass  Insulator  and  Holdfast 
complete  for          til  mch  diameter  Rope 

12s.  6d.,     10s.  6d.,     7s.  6d.,  per  set. 
Tension  Bolt,  for  tightening  and  straightening  the  wire,  of  a  simple 

form 8s,  6d. 

Glass  Insulators  annealed  with  lock  nibs         .      per  doz.  10s.  and 

Solid  Copper  Wire  Rope,  f  inch  diameter.     Price  per  100  feet     . 

Ditto  Ditto          J  inch  diameter. 

Ditto  Ditto          I-  inch  diameter. 

Price  per  100  feet 
Price  per  100  feet 


0  11  6 
0  10  0 

0  10  6 
0  14  0 
6  10  0 
3  16  0 

NOTE. — The  prices  for  Copper  goods  vary  according  to  the  market  value 
of  the  metal.     At  a  small  increase  of  cost  the  Points  can  be  strongly  gilt. 

Estimates  given  for  fitting  up  Lightning  Conductors, 
either  with  Copper  Wire  Rope,  Solid  Copper  Rod  or  Bands. 

181    Lightning  Conductors, 

The  celebrated  American  philosopher,  Franklin,  in  the  year  1749, 
first  discovered  the  means  of  averting  the  destructive  and  fatal 
effects  of  lightning  by  the  use  of  pointed  metallic  rods  attached  to 
high  and  exposed  buildings,  his  experiments  having  proved  that 
the  electric  fluid  will  always  follow  the  path  of  least  resistance  to 
the  earth. 

In  confirmation  of  the  value  of  Lightning  Conductors  as  a 
safeguard,  we  quote  the  following  from  Sir  W.  Snow  Harris  : — 

"  It  appears  from  the  records  of  the  Navy,  that  the  destructive 
effects  of  lightning  on  H.M.  ships  involved  in  former  years  an 
expenditure  of  not  less  than  from  £6,000  to  £10,000  annually.  In 
200  cases  only,  300  seamen  were  either  killed  or  hurt,  and  above 
100  large  masts  valued  at  the  time  at  from  £1,000  to  £1,200  each 
entirely  ruined.  Between  1810  and  1815,  35  sail  of  the  line,  35 
frigates  and  smaller  vessels  were  completely  disabled. 

"  Since  the  system  of  Lightning  Conductors  has  been  fully 
carried  out  in  all  H.M.  Ships,  it  appears  damage  by  lightning  has 
almost  vanished  from  the  records  of  the  Navy." 

FIG.  132. 




FIG.  133. 

134.  Magnetograph  or  Self-Recording  Magnetometer  (fig.  133), 
recommended  by  the  Meteorological  Committee  of  the  Royal  Society  and  used 
at  KQVV  Observatory.  This  apparatus,  invented  and  arranged  by  Mr.  Beckley, 
records  the  variations  continually  occurring  in  the  Earth's  Magnetism  by  the 
aid  of  photography.  Three  drums  or  cylinders,  to  which  are  attached  sheets  of 
sensitised  paper,  are  revolved  by  a  clock  movement  (seen  in  the  centre  of  the 
engraving),  and  receive  the  rays  of  light  projected  from  small  mirrors  attached 
to  each  of  the  three  magnets  so  arranged  as  to  exhibit  all  the  variations  of 
Magnetic  Force,  Inclination,  Direction,  and  Intensity.  The  lights  used  are  Gas 
Burners  or  Paraffin  Lamps. 

Our  limited  space  will  not  permit  our  giving  full  details  of  the  various 
mechanical  contrivances  made  use  of  in  this  apparatus,  which  in  many 
respects  are  somewhat  similar  to  those  employed  in  the  Recordiag  Barograph, 
Thermograph,  and  Hygrometer  shown  on  pages  30  and  78. 

The  Magnetograph  is  supplied  by  Negretti  and  Zambra  to  special  order. 

Price  £350  to  £500 

45,   COKNHILL,    E.G.,   AND    122,    REGENT   STREET,    W.,    LONDON.  131 

135.  Unifilar    Magnetometer,   Kew  Pattern,   Portable   arrangement, 
packed  in  two  boxes  complete.  Price,  £70    0    0 

136.  Kew    Pattern    Dip    Circle,    or    Inclinometer,    of    the    most 
recently  improved  arrangement,  complete,  with  Lloyd's  Total  Force  Apparatus 
and  Kew  Verification.  Price,    £35    0    0 

137.  Seismograph,  Professor  Palmeri's  recently  improved  arrangement 
for  recording  and  measuring  the  various  Volcanic  and  subterranean  tremors 
and  disturbances  of  the  Earth.  Price  complete  in  Glass  Cases,  £150    0    0 

138.  Van  Rysselberghe's  Universal  Meteorograph.     For  recording 
by   the  aid   of   Electricity  the   indications  of   Meteorological    Instruments  at 
regulated   periods   of    time.     These  records  are  registered    upon   a   metallic 
surface   every   15    minutes,    and   from  them  any  number  of    copies   can    be 
produced.     Similar  to  N".  &  Z's.  Recording  Thermometers  and  Hygrometers, 
Nos.  74  and  103,  the  Meteorograph  can  be  constructed  to  register  indications 
of  meteorologic  apparatus  in  action  at  a  great  distance  from  the  observing 
station.     The  simplest  arrangement  of    this  apparatus  includes  a  Barometer, 
Hygrometer,  Rain  Gauge,  and  Anemometer,  with  Direction  Vane.     Complete 
with  Galvanic  Batteries  and  a  supply  of  Sheets  of  Zinc,  &c.     Price,    £240    0    0 

This  price  will  vary  with  the  number  of  Instruments  of  which  records  are 

139.  Solar  Intensity  Apparatus,  Padre  Secchi's,  for  measuring  the 
comparative  heat  of  the  Sun's  Rays. 

Price  complete  with  three  Thermometers,  £440 

140.  Piche's  Evaporimeter  with  graduated  glass  Tube. 

Price,     £0  13     0 

141.  Pocket  Spectroscope,    for  observing   the  Rain  Band,  fixed  slit, 
in  Leather  Case.  Price,  £1  15    0 

142.  Ditto     Ditto     with  adjustable  slit  and  Leather  Case. 

Price,  £2  10    0 

143.  Direct  Vision  Rain  Band  Spectroscope,   larger  size,  of  very 
great  dispersive  power,  in  Leather  case.  Price,  £550 

For  further  description  and  prices  of  Electrical  Galvanic,  Magnetic  and 
Electro-Magnetic  Instruments  and  Apparatus ,  see  special  sections  at  end  of  this 









The  method  of  keeping  the 
Barometer  and  Thermometer 
Charts  is  well  shown  in  our 
diagram,  (fig.  134).  This  is  an 
actual  reprint  from  a  Chart  pub- 
lished in  the  Daily  Telegraph 
newspaper,  of  the  morning  of 
May  21st,  1877. 

By  a  most  ingenious  arrange- 
ment of  fixed  and  movable»types 
invented  by  Negretti  and  Zambra, 
the  rise  and  fall  of  the  mercury 
in  the  Barometer  tube  (as  indi- 
cated by  Negretti  and  Zambra's 
Recording  Barometer)  is  pub- 
blished  every  morning  in  the 
Daily  Telegraph,  the  diagram 
exhibiting  the  indications  of  the 
Barometer  for  the  previous  four 
days  and  to  within  a  few  hours 
of  going  to  press. 

Modifications  of  this  method  of  publishing  a  daily  Barometrical  record 
have  been  carried  out  by  the  firm  for  several  other  daily  papers,  and  in  varying 
forms  are  now  used  by  almost  every  daily  and  weekly  newspaper. 

FIG.  134. 

The  above  chart  represents  the  movement  of  the 
oarometer.  corrected  for  sea-level  and  reduced  to  32°  F., 
during  the  last  four  days  ending  midnight,  May  20-21. 

GENERAL  REMARKS. — A  return  of  a  north-easterly 
wind,  accompanied  by  occasional  showers  of  drizzling 
rain,  caused  the  weather  yesteiday  to  be  very  bleak  and 
unseasonable*  The  barometer  rose  throughout  the  day, 
the  reading  at  midnight  being  80'  11. 

DOVER. — Fine  and  cold  ;  wind  S.W. ;  sea  rough  j 
bar.  steady. 



Each  sheet  is  ruled  and  figured  for  one  month's  observations ;  twelve  of  these 
sheets  are  neatly  mounted  on  a  card,  so  that  when  one  month's  readings  are 
ended  the  sheet  can  be  removed  by  cutting  round  the  edge  with  a  sharp  knife, 
and  a  fresh  sheet  will  be  exposed.  These  records  form  a  most  interesting  and 
valuable  reference  for  comparing  present  and  past  weather. 

Price  of  each  pad  of  12  sheets,  for  Barometer,  2s.  6d. 

Ditto  ditto  for  Thermometer,  2s.  6d. 

Combined      ditto  for  Barometer,  Thermometer,  Hygrometer,  Eainfall,  &c.,  2s.  6d. 

These  Pads  of  Charts  can  be  forwarded  by  Book  Post  for  Fourpence. 

Ruled  Cliaris  or  Diagrams  for  the  Recording  Barometer,  fig.  21,  and  Recording  Aneroid 

Barometer,  figs.  28  and  29 price,  per  hundred      £150 

Ditto  Ditto,  for  Recording  Anemometers,  figs.  117.  118  and  118*          „  150 

Ditto  Ditto,  Ditto,  Tide  Gauges,  figs.  125  and  126  1     1    0 

45,    COBNHILL,   E.C.,    AND    122,   EEGENT   STEEET,   TV.,    LONDON.  133 



Price  5s. 

of  their  Scientific  Principles,  Method  of  Construction,  and  Practical 
Utility,  by  NEGEETTI  AND  ZAMBEA.  Numerous  Tables  of  Reference  in 
connection  with  Meteorology.  Illustrated  with  100  Engravings.  Price  5s. 

HYGRO METRICAL  TABLES,  Adapted  to  the  use  [of  Negretti  and  Zambra's 
Wet  and  Dry  Bulb  Thermometer,  by  J.  GLAISHEE.  Esq.,  F.R.S.  Price  2s.  6d. 

observations  to  the  32°  Fahrenheit,  for  Barometers  with  Brass  scales  ex- 
tending to  the  top  of  the  mercurial  column.  By  J.  GLAISHER,  Esq.,  F.R.S. 

Price  Is.  6d. 

JAMES  GLAISHEE,  Esq.,  F.R.S.  New  Edition.  Price  Is.  6d. 

TABLES  FOR  CALCULATION  OF  HEIGHTS  from  Observations  on  the 
Boiling  Point  of  Water,  arranged  for  use  with  Negretti  and  Zambra's 
Boiling  Point  or  Hypsometric  Apparatus.  By  the  late  Mr.  WELCH,  of 
the  Kew  Observatory.  Price  Is. 

compiled  by  Admiral  FiTZ-RoY,  F.R.S.,  &c.,  for  the  Board  of  Trade. 

Published  by  NEGEETTI  AND  ZAMBEA  with  permission     Price  6d. 

ponding Numbers  of  Elevation  in  English  Feet,  and  of  Readings  of 
Aneroid  or  Corrected  Barometer  in  English  Inches  ;  (the  Mean  of  Atmos- 
pheric Temperatures  being  50°  Fahrenheit).  Compiled  by  the  late 
Astronomer  Royal  for  NEGEETTI  AND  ZAMBEA.  Price  6d. 


Translated  by  C.  Y.  WALKER,  Esq.  Price  12s.  6d. 

(Strachan's)  with  Diagrams  for  exhibiting  the  Fluctuations  of  the  Baro- 
meter, Thermometer  and  Hygrometer.  NEGEETTI  AND  ZAMBEA.  Price  2s.  6d. 

SYMONS',  G.  J.     British  Rainfall  (published  annually  since  1865).      each  5s. 
Monthly  Meteorological  Magazine,  Vols.  I.  to  XIX.  each  5s. 

SYMONS',  G.  J.   Meteorological  Register,  with  Instructions,  for  one  year,  2s. 
„  „  „       for  five  years,  7s.  6d. 

SYMONS',  G.  J.    Blank  Diagrams  for  Barometer  and  Thermometer, 

for  one  year,  Is. 

SYMONS',  G.  J.  Blank  Rainfall  Register  for  one  year,  3d. 



THE  ordinary  household  Barometers  or  Weather  Glasses  are  constructed  in 
two  forms,  viz.,  the  Wheel  or  Dial  Barometer,  and  the  Pediment  or  Upright 
Barometer.  The  former  reading  by  an  extended  circular  scale,  and  the  latter 
from  the  actual  mercurial  column. 

The  Dial  Barometer  is  mounted  with  the  syphon  form  of  tube  as  shown 
in  our  Diagram,  the  shorter  -limb  of  the  syphon  being  about  six  or  eight  inches 
long.  This  obviates  the  use  of  a  cistern,  for  with  sufficient  mercury  in  the 
short  tube,  that  in  the  longer  one  will  be  balanced  at  a  varying  height  in 
accordance  with  the  increased  or  diminished  pressure  of  the  atmosphere. 

This  form  of  Barometer  was  first  constructed  by  the  celebrated  philosopher 
Dr.  Hook,  in  1667 ;  the  principal  advantage  of  the  dial  arrangement  is  that  by 
it  a  small  movement  in  the  mercurial  column  is  magnified  and  made  very 
apparent,  a  tenth  of  an  inch  rise  or  fall  being  represented  by  the  index  moving 
over  nearly  one  inch  on  the  dial ;  this  enables  the  unscientifiVobserver  to  notice 
quickly  if  the  Barometer  be  rising  or  falling  and  estimate  the  probability  of 
fine  or  wet  weather. 

On  the  top  of  the  mercury  in  the  short  limb  of  the  tube  is  suspended  a 
glass  float,  by  a  silk  cord  which  passes  two  or  three  times  round  a  small  brass 
wheel  or  pulley  ;  at  the  other  end  of  this  silk  cord  is  placed  a  counterpoising 
glass  weight,  moving  freely  in  a  second  tube  placed  at  the  side  of  the  syphon 
for  the  purpose  of  steadying  the  weight. 

The  axis  of  the  pulley  is  carried  through  the  wood  frame  of  the  Barometer 
to  the  front  of  the  instrument,  where  the  movement  of  the  mercury  is  shown 
by  a  light  index  hand  attached  to  it,  traversing  a  divided  dial. 

As  the  mercury  in  the  Barometer  tube  rises,  the  silk  cord  descends, 
causing  the  index  hand  to  move  to  the  right ;  on  the  contrary,  as  the  mercury 
falls  the  index  will  be  carried  in  the  reverse  direction  to  the  left. 

The  graduations  on  the  dial  represent  the  actual  inches  of  a  Standard 
Barometer  Scale,  extended  as  previously  described,  giving  what  is  termed  a 
very  open  scale. 

If  the  mercury  rises  half  an  inch  in  the  long  tube  it  will  fall  half  an  inch 
in  the  shorter  one.  Therefore,  as  the  mercury  rises  half  an  inch  in  the  one 
tube  and  falls  half  an  inch  in  the  other,  the  length  of  the  barometrical  column 
has  increased  one  inch, — but  the  movement  has  only  been  through  half  an  inch 
— this  amount  of  movement  transferred  to  the  pulley  causes  the  index  hand  to 
indicate  an  inch  movement  on  the  dial,  say  from  twenty-nine  to  thirty  inches. 

45,  COENHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON. 


145.  Our     engraving    (fig.    135)     exhibits     the 
general  internal  arrangement  of  the  Dial  Barometer. 

A  B  is  the  mercurial  syphon  tube,  and  at  W  is 
seen  the  glass  weight  or  float  attached  to  a  silk  cord. 
This  weight  floats  upon  the  surface  of  the  mercury 
rising  or  falling  in  the  tube  in  accordance  with  the 
movement  of  the  mercurial  column;  by  the  side  of 
the  syphon  is  a  second  guide  tube,  D,  for  the  counter- 
poise weight  C,  at  P  is  shown  the  pulley  over  which 
the  silk  cord  passes  giving  movement  to  the  index  hand 
over  the  Dial  as  previously  described. 

At  the  side  of  the  diagram  we  show  a  wire  plug,  E, 
used  for  making  these  barometers  portable  for  travelling 
or  exportation.  It  is  simply  a  stiff  wire  covered  witb 
cotton  throughout  its  whole  length,  and  as  will  be 
seen  in  the  drawing,  it  has  sufficient  cotton  woand 
round  the  lower  end  to  fit  the  mercurial  tube  tightly  at 
two  points, 


146.  By  inclining   the    Barometer    the   mercury 
is  caused  to  fill  the  tube  entirely,  the  float  is  then  with- 
drawn  from  the  mercurial  tube  W  (carefully  avoiding 
disturbing    the    silk     cords, — most   of     Negretti    and 
Zambra's    Barometers    are    now    fitted    with  a  brass 
clamp   to   secure  the   cords),   and  then  the  plug  E  is 

FIG.  135.  forced  slowly  down  the  tube  until  the  mercury  is 

perfectly  secured.  The  glass  float  being  placed  at  the  side  of  the  syphon  and 
secured  with  a  little  soft  packing  carefully  placed  round  it  and  the  glass  tubes, 
the  instrument  is  now  made  portable  or  secure  for  transit. 

We  need  hardly  point  out  that  the  Dial  Barometer  must  not  be  regarded 
as  an  instrument  of  precision,  but  simply  as  a  weather  indicator  or  household 

Instructions  for  setting  the  Barometer  in  action  will  be  sent  with  each 
instrument  if  it  has  been  made  portable. 

The  absolute  height  of  the  Barometer,  at  any  moment,  does  not  always  indicate  present 
weather.  The  rise  or  fall  of  the  mercurial  column  supplies  the  information  of  coming 
weather  or  change. 

A  rapid  rise  or  fall  indicates  changeable  and  unsettled  weather. 

A  falling  Barometer  and  rising  Thermometer,  are  commonly  and  quickly  followed  by  rain. 

"The  longer  the  time  between  the  signs  and  the  change  they  foretell,  the  longer  will 
the  altered  weather  last  ;  and  the  shorter  between  the  warning  and  the  change,  the  shorter 
the  continuance  of  the  changed  weather." 

"  A  fall,  with  a  low  Thermometer,  foretells  Snow." 

When  the  Barometer  falls  with  the  wind  S.E.,  it  is  generally  followed  by  long 
continued  Rains. 

A  rapid  fall  of  the  Barometer  is  usually  followed  by  much  wind  as  well  as  Rain. 

For  further  hints  How  to  foretell  the  Weather  see  N.  and  Z's.  Barometer  Manual, 
compiled  for  them  by  Admiral  Fixz-ROY.  Price,  post  free,  Sixpence. 




FIG.  159.  FIG.  158.  FIG.  159*. 

BAROMETERS  being  now  mounted  in  so  many  varied  styles,  both  plain  and  carved, 
the  following  are  given  as  a  few  specimens  of  those  most  in  demand.  Large  stocks 
of  these  instruments  are  always  kept  at  all  of  ISTEGRETTi  and  ZAMBRA'S 
establishments  of  most  of  the  patterns  shown  in  the  engravings.  Barometers 
supplied  to  order  of  any  style  of  Architecture,  to  correspond  with  the  furniture  of 
Libraries,  Halls,  &c, 

NOTE.— The  marginal  Nos.  from  this  page  will  as  far  as  possible  correspond  with  those  of  the  woodcuts. 

45,   COENHILL,    B.C.,   AND    122,    EEGENT    STRKET,    W.,    LONDON. 









FIG.  154. 

£   s.    d. 


£   s.    d. 

1  10 

2  10 

3  10 


FIG.  153.  FIG.  150. 

8-inch    Silvered     Brass    Dial    Barometer,    common, 

mounted  in  mahogany  or  rosewood  frame,  with  or 

without  mirror,  hygrometer,  and  level 
8 -inch  ditto  ditto,  square  bottom 

Ditto,  ditto,  superior  finish,  engraving,  and  large  tube 
10-inch  Silvered  Brass   Dial  Barometer,   in  common 

mahogany  or  rosewood  frame,  with  or  without  mirror, 

hygrometer  and  level  (fig.  150) 2 

Ditto,  Ditto,  square  bottom  (fig.  151)     2 

Ditto,   Ditto,  Extra  best  both  as  regards  frame,  dial, 

engraving  and  tube  (figs.  151  or  154)    .         .         .         .     3  10    0        440 

12-inch  Dial  Barometers  of  the  same  patterns,  15s.  to  £1  5s.  extra. 
8-inch  Scroll  Pattern  Dial  Barometer,    best  mounted 

mahogany,  oak,  walnut,  or  rosewood  frames,  silvered 

brass  dial,  with  Thermometer  (fig.  153) 

10  and  12-inch  Scroll  Pattern  Barometers,  20s.  to  50s.  extra. 

8-inch  Dial  Barometer,  with  ornamental  figures,  letters, 

and  'divisions   on  PATENT  ENAMELLED  GLASS   DIAL 

(fig.  154) , 

8-inch  Dial  Barometer,  rosewood  frame  inlaid  with  PEARL 

or  METAL,  with  silvered  brass  dial        .... 
10-inch  ditto,  best  rosewood  frame  inlaid  with  PEARL  or 

METAL,  the  dial  of  silvered  metal,  with  Thermometer, 

superior  finish  Nos.  155  &  156  fitted  up  to  order  (fig.  156) 

12  and  14-inch  Dial  Barometers  ditto,  at  proportionate  prices. 

330        440 



12  12    0 



FIG.  156. 

Fm.  157. 

FIG.  158*. 




0    0 



14-inch  Dial  Barometer,  best  rosewood  frame  inlaid  with  PEARL  or 
METAL,  the  dial  of  silvered  metal,  and  an  eight-day  Clock  fitted  in 
the  frame,  Thermometer,  &c.  (fig.  157)  fitted  up  to  order  .  .  25 

8  and  10-inch  Dial  Barometers,  plain  carved,  in  solid  oak,  mahogany, 
rosewood,  or  walnut  frame,  double  basil  ring,  and  polished-edge 
plate  glass,  of  the  very  best  construction  and  superior  engraving, 
as  figs.  158  and  158* £5  5s.  £6.  6s.  to  8  8  0 

Dial  Barometers,  10, 12,  and  14-inch,  of  the  very  best  construction, 
in  richly  carved  solid  frames  of  Gothic,  Mediaeval,  Elizabethan, 
Egyptian,  Chippendale  or  other  designs,  in  Oak,  Mahogany,  or 
Walnut-wood  (figs.  159  and  159*)  .  /  £10  10s.  £16  16s.  to  25  0  0 

Suitable  for  Club-houses,  Mansions,  &c. 

N.B. — DIAL  BAROMETERS  required  for  transmission  to  distant  parts,  such  as  India  or  the  Colonies,  should 
be  ordered  expressly,  as  in  that  case  they  will  be  rendered  portable  by  plugging  the  tube  as  described 
page  135,  and  shown  in  diagram  fig.  135. 

The  prices  quoted  for  the  more  elaborate  forms  of  Dial  Barometers  are  subject  to  variations  dependent 
upon  the  amount  and  quality  of  the  ornamental  carving  and  engraving. 

45,    COBNF1ILL,   E.G.,   AND   122,   BEGENT   STREET,   W.,    LONDON.  139 


NEXT  to  a  Standard  instrument  the  Pediment  Barometer  must  be  regarded  in 
a  scientific  point  of  view  as  the  most  accurate  form  of  Barometer,  the  actual 
weight  or  pressure  of  the  atmosphere  being  exhibited  by  the  varying  length  of 
the  mercurial  column  itself,  subject  to  a  few  corrections  that  need  not  be  noticed 
by  ordinary  observers.  At  pages  2  and  3  will  be  found  the  general  principles 
of  the  straight  tube  or  Pediment  Barometer. 

The  cistern  of  the  Pediment  Barometer  is  made  of  boxwood,  with  sufficient 
internal  area  to  allow  of  a  fall  of  at  least  two- thirds  of  the  mercury  contained 
in  the  tube  when  the  Barometer  is  in  action  without  materially  interfering  with 
the  correctness  of  the  readings.  It  should  also  contain  sufficient  mercury  to 
prevent  air  passing  up  into  the  tube.  The  bottom  of  the  cistern  is  formed  of 
flexible  leather,  so  as  to  admit  of  the  use  of  a  screw  to  render  the  Barometer 
portable,  as  described  in  the  paragraph — Standard  Barometer,  pages  4  and  5. 

It  will  be  seen  that  most  of  these  Barometers  are  furnished  with  two  Verniers, 
or  indices.  The  use  of  the  second  Vernier  is  to  record  on  the  left  hand  scale  of 
the  instrument  the  previous  reading  of  the  Barometer,  and  show  at  a  glance 
any  alteration  that  may  have  taken  place  by  the  difference  of  the  readings  of 
the  two  Verniers. 

In  taking  a  reading  or  observation  by  the  Pediment  Barometer  the  Vernier 
carrying  the  Index  Pointer  is  to  be  moved  gently  up  or  down,  until  its  edge  is 
exactly  in  a  line  with  the  centre  of  the  top  of  the  mercurial  column  as  shown 
in  fig.  5,  page  6.  If  when  adjusted  the  edge  of  the  index  is  exactly  in  a 
straight  line  with,  say,  the  division  marked  30,  then  the  height  or  length  of  the 
mercurial  column  is  exactly  thirty  inches.  The  value  of  this  column  is  given  on 
pages  4  and  5 ;  also  on  pages  6  and  7  will  be  found  a  description  of  the  use 
of  the  Vernier,  especially  at  the  foot  of  page  7,  where  the  Vernier  of  the 
ordinary  Household  Barometer  is  spoken  of  as  subdividing  the  inch  scale  into 

If  the  division  1  in  the  Vernier  coincides  with  the  line  at  29  inches  on  the 
scale,  then  the  reading  would  be  29'11;  if  division  2  coincides  with  the  line 
below  that  marked  29  inches,  then  the  reading  would  be  29'12 ;  that  is  twenty- 
nine  inches  and  eleven  hundredths  or  twenty-nine  inches  and  twelve  hundredths, 
or  it  may  be  read  twenty-nine  inches  one  tenth  and  one  hundredth,  and  so  on. 
The  allowance  to  be  made  for  height  of  the  Station  above  the  sea-level  is,  as 
stated  by  Admiral  Fitz-Roy,  as  under. 

The  average  height  of  the  barometer,  in  England,  at  the  sea-level,  is  about 
29*94  inches,  and  the  average  temperature  of  air  is  nearly  50  degrees. 

Every  ten  feet  of  elevation  above  the  sea  lowers  the  Barometer  about  ten 
or  eleven  thousandths  of  an  inch. 

Add  one-tenth  of  an  inch  to  the  observed  height  for  each  hundred  feet  the 
Barometer  is  above  the  mean  sea-level.  This  sea-level  should  be  that  of  the 
ocean  itself,  at  mean  half-tide,  a  level  which  should  be  the  universal  standard 
line  of  reference. 

The  Thermometer  falls  about  one  degree  for  each  three  hundred  feet  of 
elevation  above  more  than  fifty  feet  from  the  ground. 




FIG.  168. 

FIG.  169. 

FIG.  168*. 

45,   CORNHILL,   E.G.,   AND    122,    EEGENT   STEEET,   W.,   LONDON. 

FIG.  165. 

FIG,  161. 

FIG.  164. 

FIG.  163. 

FIG.  164*. 


160  Model  Barometer,  with  vernier  and  thermometer,  also 

screw,  to  render  it  portable  ...... 

161  Pediment  Barometers,  with  ivory  scales,  thermometer, 

SLIDING  VERNIER,  the  tube  visible  throughout  the 
whole  length,  and  portable  screw,  (fig.  161) 

162  Pediment  Barometer,  with  glass  cover  over  the  face, 

rackwork  vernier  and  thermometer,  exposed  tube 

163  Portable  Pediment  Barometer,  Round  Top  Frame  in, 

Oak,  Mahogany  or  Rosewood,  the  tube  covered 
entirely,  rackwork  Yernier,  and  a  Thermometer  on 
the  front  (fig.  163)  ...  .... 

164  Ditto     ditto,  with  Square  Moulded  Top,  large  tube,  and 

one  Yernier  (figs.  164  and  164*) 

165  Ditto  ditto,  with  extra  large  tube,  2  rackwork  verniers, 

ivory  scales,  with  Thermometer,  in  Oak,  Mahogany, 
Walnut,  or  Rosewood  frame  (fig.  165)  .... 

£    s.    d. 


£    s.    d. 


2  10    0 

2  15    0 


3  10    0        4  10    0 

550        660 



FIG.  166. 

FIG.  167. 

FIG.  167A. 

FIG.  167B.       FIG.  I67c. 

FIG.  167D. 


166  Portable  Pediment  Rosewood   Barometer,  elegantly  inlaid  with 

pearl  or  metal,  thermometer  in  front,  ivory  scale,  rackwork  vernier 

(fig.  166) fitted  up  to  order     770, 

167  Portable  Pediment  Barometers,  with  two  Verniers,  best  Carved  oak, 

Rosewood,  "Walnut,  or  Mahogany  frames,  of  various  elegant  designs, 
fitted  up  in  the  very  best  manner  (figs.  167  and  167  A,  B,  c,  D). 
with  Opal  Glass  or  Ivory  Scales  £6  6s.  £8  8s.  10  10  0 

168  Large  Pediment  Barometers,  handsomely  mounted  in  Oak,  Walnut, 

or  Ebonised  frames,  the  tube  of  large  internal  diameter,  and 
the  cistern  presenting  a  large  area,  to  insure  uniformity  in 
reading,  Ivory,  Opal  Glass,  or  Silvered  Metal  Scales,  with 
engraved  ornamental  letters  and  two  Yerniers  (figs.  168  and  168*) 

£8    8s.    £10    10s.    £12    12s.  15  15    0 

169  Ditto        ditto,       Ebonised    Wood    frames    with    Ivory    or    Opal 

Glass     Scales,    and    two     Yerniers     very    handsomely    carved 

(fig.  169)         .        . £1818    0  to  26    0    0 

Extra  sized  Pediment  Barometers,  suitable  for  Public  Institutions  or  Club  Houses, 
specially  designed  and  made  with  English  or  French  and  English  Scales  to  order. 

A  large  and  varied  Stock  of  Household  Barometers  will  always  be  found 
at  all  of  Negr.etti  and  Zambra's  Establishments. 

45,   COENHILL,    E.C.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  171. 

BAROMETER,  as  made  by  Negretti  and  Zambra 
especially  for  the  Board  of  Trade  and  Royal  Life 
Boat  Institution,  to  be  fixed  at  all  the  principal 
Seaports,  Fishing  and  Life  Boat  Stations. 

fig.  170.       Price,  £5    5s. 

This  Barometer  consists  of  a  tube  with  very  large  bore,  and  an 
accurate  Thermometer,  mounted  in  a  solid  oak  frame,  firmly  screwed 
together,  with  scales  and  figures,  &c.,  permanently  engraved  on  Porce- 
lain, by  Negretti  and  Zambra's  Patent  process,  the  Vernier  reading  to 
100-ths  of  an  inch.  It  is  strongly  recommended  as  a  good,  sound 
working  instrument,  admirably  adapted  for  use  in  Public  Institutions. 

Extract  from,  Admiral  Fiti-Rc^fs  Reports  of  the  Meteorologio  Office 
of  the  Board  of  Trade,  1864  :— 

"In  my  last  Report,  I  stated  how  highly  the  Board  of  Trade 
'  Fishery '  Barometers  have  been  valued  on  the  coasts.  They  are  now 
eighty  in  all,  specially  lent,  under  due  control  and  care.  Two  only  of 
this  number  have  become  slightly  defective,  and  have  been  exchanged . 
Not  one  has  been  injured  in  carriage,  singular  to  say,  between  Cornwall 
and  the  Shetland  Isles,  Ireland  and  Yorkshire.  It  may  be  more  readily 
estimated  mentally  than  accurately  proved,  to  what  extent  these  simple 
instruments  (all  reliably  madef  and  tested)  have  already  been  the  means 
of  saving  life  and  property.  Explanatory  manuals  and  blank  forms  for 
diagrams  have  been  extensively  circulated  among  the  coasters  and 
fishermen,  who  are  all,  now,  much  influenced  by,  and  very  thankful  for, 
the  benefits  of  this  act  of  their  Government.  Many  are  the  local  in- 
stances of  similar  beneficence  by  individuals — especially  the  Duke  of 
Northumberland,  who  has  placed  no  less  than  fourteen  barometers." 

Messrs.  Negretti  and  Zambra  would  specially  caution  the 
Public  against  purchasing  cheap  and  worthless  imitations  of 
Admiral  Fitz-B-oy's  Barometers  as  leading  to  disappointment. 
Full  details  both  as  to  the  construction  and  use'of  the  true  Fitz-Roy 
instrument  will  be  found  in  Negretti  and  Zambra's  Barometer 
Manual,  compiled  by  Admiral  Fitz-Roy  for  the  Board  of  Trade  ; 

post  free,  6d. 

171  Fitz-Roy  Barometers  with  two  Verniers     .       .  £6  10    0 

172  Ditto      ditto,      in     Ornamental     Carved    Oak, 

Walnut,  or  Mahogany  frames  (fig.  168*)  .  .880 
Barometers  in  solid  frames,  mounted  wilh  Ivory  or  Opal 
Glass  Scales,  having  the  Fitz-Roy  Weather  Rules  on  one  side 
and  the  ordinary  words,  Fair,  Change,  Rain,  and  Stormy  on 
the  other,  at  the  same  prices  as  No.  168*.  These  instru- 
ments are  very  suitable  for  Public  Institutions. 

t  By  Messrs.  Negretti  and  Zambra. 


FIG.  173. 

173  Negretti  and  Zambia's  Faimer's  Baiometer,  for  ascer- 
taining the  humidity  of  the  atmosphere,  the  general  character  of 
the  weather,  and  the  approach  of  wind  or  rain.  The  Farmer's 
Barometer  combines  three  distinct  instruments — the  Barometer, 
the  Thermometer,  and  the  Hygrometer,  and  is  equally  valuable  to 
the  Agriculturist  and  the  Invalid,  a  difference  of  5°  to  8°  being 
considered  a  healthy  amount  of  moisture  in  the  air  of  dwelling 
rooms.  The  action  is  very  simple,  and  so  long  as  a  sufficient 
supply  of  water  is  kept  in  the  cistern,  the  Hygrometric  condition 
of  the  atmosphere  can  be  known  at  any  moment. 

It  is  a  well-known  fact  that  the  Barometer  is  as  much,  or  even 
more  affected  by  a  change  of  wind  as  it  is  by  rain,  and  the  ob- 
jection raised  against  a  simple  Barometer  reading,  as  leaving  the 
observer  in  doubt  whether  to  expect  rain  or  wind,  is  entirely  re- 
moved in  the  instrument  now  offered  to  the  Public  by  the  addition 
of  the  Hygrometer,  an  instrument  indicating  the  comparative 
degree  of  dryness  or  dampness  of  the  air ; — a  most  important 
item  in  the  determination  of  the  coming  weather. 

Hitherto  the  use  of  scientific  instruments  of  this  class  has 
been  confined  to  very  few  observers.  Nevertheless,  through 
the  instrumentality  of  James  Glaisher,  Esq.,  F.R.S.,  as  Secretary 
of  the  British  Meteorological  Society,  multitudes  of  observations 
have  been  taken  with  extreme  accuracy,  and  duly  registered ; 
and  it  is  from  these  carefully  collected  data  that  we  are  enabled 
in  a  measure  to  interpret  the  various  changes  that  we  feel  and 
see  going  on  in  our  atmosphere,  and  by  the  aidj  of  well-con- 
structed instruments,  are  in  a  position  to  predict  with  a  great 
degree  of  certainty  the  weather  that  is  likely  to  prevail  from 
time  to  time. 

Instructions  for  using  the  Wet  and  Dry  Bulb  Hygrometer 
will  be  found  at  page  77.  And  at  page  76  will  be  found  a  table 
giving  the  value  of  Hygrometric  readings  in  a  simple  form, 
sufficient  for  the  use  of  ordinary  observers. 

The  Fanner's  Barometer  as  fig.  173    ....       £2  10s. 
Ditto,  ditto,  in  Ornamental  Mountings    £5  5s.     £6    6s. 

174  Negretti  and  Zambra's  Miners'  Barometer. — It  having 
been  observed,  that  explosions  of  gas  in  mines  mostly  occur  when 
the  Barometer  is  very  low  (showing  diminished  atmospheric  pres- 
sure), it  is  important  that  a  good  Barometer  should  be  at  hand, 
for  observation  by  the  Managers  and  others.  For  this  purpose 
Negretti  and  Zambra  make  strong  and  sufficiently  accurate 
Barometers,  as  fig.  174,  at  .  .  £1  Is.  £2  2s.  £3  3s. 

175  Aneroid  Barometers  for  Miners'  use,  exceedingly  convenient  and  sensitive, 

with  Extended  Scale £2  10s.     £3  10s.     £4  4s. 

176  Miners'  Pocket  Aneroids,  see  also  page  143. 

£3    3s.    £4    4s.    £5    5s. 

STANDARD  AND  MOUNTAIN  BAROMETERS  (see  pages  1  to  13). 

45,    COENHILL,    E.G.,   AND    122,    EEGENT   STREET,   W.,    LONDON.  145 

FIG    174. 

FIG.  177. 

FIG.  181. 

FIG.  180.       FIG.  179. 


177  Marine  Barometer,  plain  mahogany  frame,  with  Ivory 

scales,  sliding  vernier,  Thermometer,  and  Brass  arm 
gimbal,  for  suspension  (fig.  177) 

178  Marine    Barometer,    round,    moulded,   or  carved  top, 

with  rack- work  to  vernier,  Thermometer,  capillary  tube 
to  prevent  the  ingress  of  air  into  the  column,  even 
during  the  most  violent  oscillations  of  a  storm, 
Brass  arm  gimbal,  &c.  ....... 

179  Ditto  ditto,  in  Carved  frame  (fig.  179)       .... 

180  Marine  Barometer,  best  mounted  as  fig.  180  . 

181  Marine  Barometer,  best,  with  SYMPIESOMETER  in  front ; 

the  sympiesometer  constructed  and  laid  off  with  the 
greatest  accuracy  by  actual  experiments,  Brass  gimbal, 
&c.  (fig.  181) 

182  Board  of  Trade  Standard  or  Kew  Marine  Barometer, 

figs.  16  (seepage  11)  and  182. 

183  Fitz-Roy's  Marine  Gun  Barometer,  fig.  183,  (see  page  12). 

£    s.    d. 

£    s.    d. 

220        2  10    0 





FIG.  186. 

FIG.  187. 


184  Sympiesometers.  Previous  to  the  invention  of  the  Aneroid 
Barometer,  the  Sympiesometer,  from  its  extreme  sensibility  and  con- 
venient size,  was  much  used  for  Marine  observations ;  but  owing  to 
its  liability  to  be  put  out  of  adjustment  in  transit,  it  is  now  rarely 
used  except  as  an  instrument  of  comparison.  Being  partly  acted  upon 
by  the  pressure  and  partly  by  the  temperature  of  the  air,  its  correct 
name  would  be  a  Thermo-Barometer. 

Directions  for  using  the  Sympiesometer. — It  should  be  always 
carried  top  upwards,  to  prevent  the  air  mixing  with  the  liquid.  Care 
should  always  be  taken  to  screen  it  from  the  heat  of  the  sun  or  cabin 
fire.  To  ascertain  the  atmospheric  pressure  by  the  Sympiesometer, 
note  first  the  temperature  of  the  mercurial  thermometer;  secondly, 
adjust  the  pointer  of  the  pressure  scale  to  the  same  degree  of  temperature  on  the 
scale  of  the  air  column ;  thirdly,  read  the  height  of  the  liquid  on  the  sliding  scale, 
the  divisions  and  figures  representing  the  inches  and  tenths  of  theJBarometer  scale. 


185  Sympiesometer,  in  wood  frame,  with  registering  index 

and  plate  glass  front 

186  Ditto  ditto,  with  Hackwork  Movement,  large  size  and 

best  make,  Oak  or  Rosewood  Frame  (fig.  186)     . 

187  Pocket   Sympiesometer,*  suitable    for    travelling,  and 

taking  altitudes,  or  mountain  service,  in  leather  hinged 
case  (fig.  187) 

188  Ditto   ditto,  in  leather  case  with  strap  for  Mountain 

service    .  .... 

£    s. 

2  10 

4  10    0 

3  15    0 


*  The  use  of  the  Pocket  Sympiesometer  is  now  quite  superseded  by  the  Aneroid  Barometer. 

45,  COENHILL,  E.G.,  AND  122,  EEGENT  STREET,  W.,  LONDON. 


1    FIG.  190. 

FIG.  189. 

FIG  192. 

189  Storm  Glass  or  Chemical  Weather  Glass,  for  prognosticating  Each.  Each. 

changes  in  the  weather,  by  sea  or  land,  particularly 

high  winds,  storms,  or  tempests  (fig.  189)     .        .         .046        056 

190  Ditto        ditto    mounted  on  a    Boxwood  Scale,    with 

a  Thermometer  (fig.  190)       .        .        .        .       7s.  6d.    0  10    6        0  12    6 

191  Ditto        ditto   .        .    plain  Window  Bracket        .  0  12    6 

192  Ditto        ditto  best,  mounted  on  Window  Bracket(fig.  192)     110        1  15    0 
This  curious  instrument  appears  to  have  been  invented  more  than  a  hundred 

years  ago.  The  original  maker  is  not  known;  but  doubtless  it  is  an  accidental 
discovery  of  some  of  the  old  Alchemists,  who  were  constantly  experimenting  with 
the  substances  composing  the  solution  with  which  it  is  made.  It  is  simply  a  long 
glass  vial,  nearly  filled  with  an  alcoholic  solution  of  camphor,  to  which  is  added 
crystals  of  nitrate  of  potassa  and  muriate  of  ammonia,  with  a  small  proportion  of 
distilled  water.  Air  fills  the  upper  part  of  the  vial,  the  mouth  of  which  is  corked 
or  hermetically  closed. 

The  various  appearances  presented  in  the  liquid  and  crystals  have  been 
noticed  to  prognosticate  atmospheric  changes,  and  rules  have  been  deduced  from 
careful  study  and  comparison  of  the  glass  and  weather.  Instructions  for  using 
the  Chemical  Storm  Glass  sent  with  each  instrument. 

Admiral  Fitz-Roy,  in  The  Weather  Book,  writes  of  this  instrument  as  follows  : — 

"Since  1825,  we  have  generally  had  some  of  these  glasses,  as  curiosities  rather  than  otherwise;  for 
nothing  certain  could  be  made  of  their  variations  until  lately,  when  it  was  fairly  demonstrated  that  if  fixed 
undisturbed  in  free  air,  not  exposed  to  radiation,  fire,  or  sun,  but  in  the  ordinary  light  of  a  well- ventilated 
room,  preferably,  or  in  the  outer  air,  the  chemical  mixture  in  a  so-called  storm-glass  varies  in  character  with 
the  direction  of  the  wind — not  its  force,  specially  (though  it  may  so  vary  in  appearance,  only  from  another 
cause,  electrical  tension)." 

Some  curious  information  connected  with  the  Camphor  Glass  will  be  found  in  two 
pamphlets  written  by  Charles  Tomlinson,  Esq.,  of  King's  College,  London,  on  The  Move- 
ments of  Camphor  on  Water,  and  The  Motion  of  Camphor  towards  Light.  From  these  papers 
it  would  appear  that  the  changes  observed  in  the  Storm  Glass  are  due  solely  to  variations 
of  light  and  heat. 

L  2 




FIG.  194. 

FIG.  195 



Aneroid  Barometer,  Metal  Case  about  5  inches  diameter.  Enamelled  £ 
Card  Dial,  stout  Glass  front,  in  hinged  Leather  Case     .         .         .2 
Ditto        ditto,  with  Silvered  Metal  Dial  (fig.  194)      . 
Ditto        ditto,  with  Thermometer  (fig.  195) 

s.     d. 

10  0 
3  10  0 

Flu.  196. 

FIG.  199. 


Boat  Aneroid,  the  engraving  fig.  196  represents  the  exact  size  of  Negretti  and 
Zambra's  Pocket  instrument.  The  metal  case  and  the  covering  glass  is 
made  suitably  strong  for  the  use  of  Captains  or  Pilots  of  small  Coasting 
vessels.  Price,  in  Stout  Case,  £330 

45,    COBNH1LL,   B.C.,   AND   122,   REGENT   STREET,   W.,   LONDON. 


FIG.  201. 

197  Ship  or  Yacht  Aneroid  Barometers  in  strong  plain  Metal  or  ornamentally 

carved  Wood  mountings.  Extreme  convenience  of  size,  combined  with  great 
sensibility  and  reliability,  have  made  these  instruments  very  popular  for 
state  cabins  of  Sea-going  Vessels  and  Steam  Ships. 

198  Ships' Aneroids,  plain  Circular  Bronzed  Metal  Mountings, 

with  Thermometer  on  the  dial       .        .          £330550        660 

199  Ships'  Aneroids  in  handsomely  Carved  Wood  Frame  with 

Thermometer  (fig.  199) 660        880 

200  Ships'  Aneroids,         .        .        .    smaller  sizes  £3    303  10    0        440 
At  pages  21  to  29  will  be  found  a  full  description  of  the  construction  and  use 

of  various  forms  of  Aneroid  Barometers. 

201  Negretti   &   Zambra's   new   Fisherman's  Aneroid   Barometer   (fig.   201). 

No  trouble  or  expense  has  been  spared  to  obtain  a  trustworthy  instru- 
ment at  a  moderate  cost.  It  is  mounted  in  a  stout  metal  case,  with  a 
plate  glass  covering,  the  dial  is  of  enamelled  metal  and  5  inches  diameter. 
The  range  of  scale  is  26  to  31  inches,  subdivided  into  tenths,  corresponding 
with  the  scale  of  the  Mercurial  Barometer.  Price,  £1  15  0 

It  will  be  noted  that  at  the  top  of  the  Dial  is  placed  the  word  CHANGEABLE  ; 
to  the  right  and  left  of  this  word  is  printed  a  condensed  form  of  Admiral  Fitz-Roy's 
rules  for  prognosticating  the  coming  weather. 

Should  the  Blue  Index  move  to  the  right  fine  weather  may  be  anticipated ;  on 
the  contrary,  should  it  recede  to  the  left,  bad  and  stormy  weather  is  indicated. 

These  movements  correspond  with  those  of  the  Mercurial  Barometer,  hence 
the  Aneroid,  like  the  Mercurial  Instrument,  is  said  to  be  Rising,  Falling,  or 

201*    Negretti  and  Zambra's  Farmers'  Aneroid,  mounted  in  frames,  similar  to 
fig.  154.  £4  4s.,  £4  10s. 



FIG.  203. 

FIG.  205. 

FIG  204. 

FIG.  202. 

202  Aneroid  Barometers,  in  Ornamental  Mountings. 
Since  the  publication  of  the  early  editions  of  our  Illus- 
trated Catalogue  we  have  introduced  the  Aneroid  for  use 
as  a  household  Barometer,  mounting  it  in  variously 
designed  ornamental  frames,  suited  either  for  the 
Mantel  Shelf  or  for  Suspension  in  the  Hall  or  Library. 
Our  engravings  exhibit  a  few  of  the  series  we  have  had 
specially  designed  to  suit  these  instruments. 

One  very  important  advantage  of  the  Aneroid 
movement  thus  mounted  is  that  there  is  very  little  fear 
of  damage  in  transport ;  therefore  these  Barometers 
can  be  safely  sent  abroad  to  places  where  hitherto  it 
has  been  almost  impossible  to  send  a  mercurial  instru- 
ment with  safety;  for  beyond  careful  packing  (the 
Aneroid  does  not  want  any  screwing  up  or  making 

portable)  nothing  is  required  but  to  unpack  the  instrument  and  hang  it  up,  and  it 

will  at  once  be  in  action,  and  show  the  atmospheric  pressure  at  the  place  where 


For  the  saloons  of  Sea-going  Vessels  and  Yachts,  these  Aneroid  Barometers 

are  admirably  adapted,  being  convenently  small  in  size,  and  very  accurate. 

New  patterns  are  being  constantly  added  to  our  stock,  and  we  would  observe 

that  many    of    our    Dial .  Barometer     Frames    can  be    mounted    with    Aneroid 

Barometers  instead  of  Mercurial  Tubes. 

Aneroid  Barometer,  as  fig.  203, 5-inch  dial,  £5  5s. ;  fig.  203,  8-inch  dial,  £10 10s. ; 

fig.  204,  5-inch,  £6  6s. ;  fig.  204,  8-inch,  £11  11s.;  fig.  205,  £5  10s.;  fig.  205,  with 

Clock,  £10  10s. ;  fig.  202,  £18  10s.  and  £22  ;  fig.  206,  £6  10s. ;  figs.  207  and  208,  £5  5s. 

and  £6  10s. ;  fig.  209,  £18  18s. ;  Carved  frames  as  figs.  158, 158°,  pages  136  and  138, 

£6  6s.,  £7  7s.  and  £8  8s. 

45,   CORNHILL,   B.C.,   AND    122,    REGENT   STBEET,    W.,    LONDON.  151 

FIG.  206. 

FIG.  209. 




AT  pages  31  and  32  will  be  found  described  many  important  improvements  in  the 
construction  of  Thermometers  invented  and  Patented  by  NEGRETTI  AND  ZAMBRA. 
Also  the  process  for  Engine- dividing  the  Scales  and  Tubes,  for  which  a  Prize 
Medal  was  awarded  to  NEGRETTI  AND  ZAMBRA  at  the  Great  Exhibition  of  1851 
(see  fig.  31) ;  a  second  award  of  Two  Medals  in  1862,  for  many  important  im- 
provements and  inventions ;  a  Prize  Medal,  Santiago,  Chili,  1875 ;  and  also  a 
Prize  Medal  for  Thermometers,  Philadelphia,  1876.  Paris,  1878,  Gold  Medal; 
London,  1883,  Fisheries  Exhibition,  2  Gold  Medals,  1  Silver,  1  Bronze. 

These  inventions  are  applied  to  all  of  NEGRETTI  AND  ZAMBRA'S  instruments 
enumerated  in  the  following  List,  where  precise  accuracy  is  desirable. 

This  List  will  comprise  Thermometers  of  every  form  and  description,  suited 
for  Domestic,  Medical,  Horticultural,  Scientific,  and  Manufacturing  purposes, 
arranged  as  far  as  practicable  in  separate  divisions. 

Following  these  are  arranged  the  various  instruments  used  for  ascertaining 
the  Specific  Gravity  of  fluids,  known  under  the  general  term  of  Hydrometers ;  the 
whole  of  the  instruments  found  under  this  heading  with  various  names  showing 
the  same  fact,  viz.,  Specific  Gravity,  by  differing  scales,  from  the  extremely  light 
and  volatile  ^Ethers  and  Paraffins  to  the  dense  and  heavy  Sulphuric  Acid. 

In  the  appendix  to  this  catalogue  will  be  found  Rules  for  comparing  the 
various  Thermometer  and  Hydrometer  Scales  in  general  use. 

Many  years  of  practical  experience  in  the  manufacture  of  Thermometers  and 
Hydrometers  in  every  variety  of  shape  enables  NEGRETTI  AND  ZAMBRA  to  guarantee 
the  accuracy  of  these  instruments,  as  regards  testing  and  dividing  the  scales ;  at 
the  same  time,  careful  attention  is  bestowed  on  their  construction,  to  insure  the 
most  improved  forms  combined  with  the  greatest  durability. 

The  following  is  an  extract  from  a  letter,  received  by  Messrs.  NEGRETTI  AND 
ZAMBRA,  written  by  Mr.  Whipple,  the  manager  of  Kew  Observatory,  with  reference 
to  some  Thermometers  sent  down  by  the  firm  for  comparison. 

"  I  believe  I  may  again  assert  with  confidence,  that  we  have  never  yet  had  so  large  a 
number  of  low  range  Thermometers  pass  through  our  hands  exhibiting  so  high  a  degree  of 
accuracy  at  the  melting  point  of  mercury." 

45,    COENHILL,    E.G.,   AND    122,    REGENT   STREET,   W.,   LONDON. 



FIG.  221.  FIG.  240.        FIG.  217.    FIG.  214.        FIG.  213.      FIG.  219.        FIG.  217*. 

£    a.    d. 

£    s.    d. 

210  6  or  8-inch  Thermometer,  Boxwood  Scale       ...  010 

211  8 -inch  ditto,  with  French  polished  scale  016 

212  8-inch  ditto,  superior.  A  good  reliable  instrument,  suited 

for  Dormitories,  Hospital  wards,  Wine  cellars,  Stables,  &c.  026 

213  8-inch  ditto,  with  Enamel  tube,  (fig.  213)  030 

214  8 -inch  ditto,  with  Enamel  tube,  the  scale  bevelled  at 

the  edges,  with  double  scales,  either  Fahrenheit  and 

Centigrade,  or  Fahrenheit  and  Reaumur  (fig.  214)        .036        046 

215  10-inch  Best  Mounted  Single  Scale  Thermometers          .056        0    7     G 

216  12-inch  best  Mounted   Boxwood  Scale  Thermometer, 

with  double  scales  ....      10s.  6d.  12s.  6d.     0  15    0        110 

217  8-inch,   10-inch,  and  12-inch  Negretti  and    Zambra's 

Patent  Porcelain  Scale  Thermometer,  strongly  and 
neatly  mounted  on  Oak,  Very  durable  and  suited  for 
outdoor  exposure  (figs.  217  and  217*)  .  .  5s.  6d.  0  7  6  0  10  6 

218  Ditto        ditto,  with  Opal  Glass  Scales  .        .       /s.  6d.     0  10    6        0  12    6 


219  6  or  8-inch   Thermometer,  elegantly  engraved    Ivory 

Scale  on  Ebony  Back,  with  German  Silver  Mountings 

and  double  scales  (fig.  219)    ....     10s.  6d.  0  12    6        0  16    0 

220  10-inch  ditto              with  very  bold  figures  and  divisions  110 

221  12-inch  ditto,  best  mounted,  extra  large  (fig.  221)  £1 10s.  1  15    0        2    2    0 



FIG.  228. 

FIG.  223. 





£    s.    d. 

FIG.  226. 

£    s.    d. 

222  10  or  12-inch  Thermometers,  Opal  Glass  Scale,  with 

German  Silver  Mountings,  superior  workmanship,  and 
elegant  appearance,  on  Oak,  Mahogany,  or  Ebonised 
backs,  with  Negretti  and  Zambra's  Patent  Enamelled 
Tubes,  suited  for  Halls,  Dining  Rooms,  Libraries,  &c. 
(figs.  219  and  222),  the  divisions  and  figures  very 
plainly  marked.  Spirit  or  Mercurial  .  21s.  25s.  1  10  0  220 

223  Porcelain  Scale  Thermometers,  having  extra  large  tubes, 

with  very  legible  scales  and  words  (fig.  223)  : — 

Single  Scales. 

8 -inch.      Tubes  filled  with  Mercury 






Coloured  Spirit    . 


7  6 
9  6 
0  14  6 
0  12  6 

Double  Scales. 

0  10  6 
0  16  6 

0  14  6 

1  10  0 

Window     Thermometers,     Porcelain     Scales 


0  10    6        0  12    6 

Wood  Brackets 

Window  Thermometers,  8-inch  Ivory  or  Glass  Scales, 
enclosed  in  glass  cylinders,  on   Oak  Brackets,  with 

metal  tops ,         .        .     0  12    6        0  15 

10-inch  ditto        ditto  (fig.  226) 0  18 

12 -inch  ditto        ditto  150        1  10 

45,    CORNHILL,    E.G.,   AND   122,    REGENT   STREET,    W.,    LONDON. 

FIG.  236. 


FIG.  231.        FIG.  238.    FIG.  237.    FIG.  247.    FIG.  232.     FIG.  235. 

FIG.  230. 

£    s.    d. 

£    s.    d. 






Window  Thermometers,  10,  12,  or  14-inch,  Opal  Glass 
scales,  divided  by  engine,  and  handsomely  mounted  on 
Oak  Brackets,  with  brass  supports  for  fixing  at  any 
angle  (fig.  228) 21s.  1  10  0  220 


3  or  4-inch  Ivory  or  Metal  Scale  Pocket  Thermometer, 
in  morocco  leather  hinged  case  (fig.  230) 

6-inch  ditto ditto  (fig.  230)- 

8-inch  ditto ditto  (fig.  231) 

Oval  Boxwood  Pocket  or  Dressing  Case  Thermometer, 
with  tube  and  bulb  sunk  in  the  solid  Wood,  to  prevent 
breakage  in  travelling  ....  (fig.  232) 

Ditto  ditto larger 

Oval  Ivory  ditto  ditto 

Ditto  ditto  larger  size  (fig.  235) 

Negretti  and  Zambra's  Improved  Travelling 
Thermometer,  in  Metal  or  Silver  Case  (fig.  236) 

0  4 
0  6 
0  10 

0    7 
0  10 

0  16 

1  4 

0  10    6        110 

Not  larger  than  a  pencil  case; 
Clinical  Thermometer. 


accurately  divided  on  its  own  stem.     Can  he  arranged  as  a  small 

Negretti  and  Zambra's  Pocket  Travelling  Thermometer, 

German  silver  Revolving  Case,  and  Ivory  scale  (fig.  237)    0  10    6        0  15    0 

238  Ditto,  ditto,  ....    extra  large  (fig.  238)  0  18    6 

239  Pocket  Thermometer  in  Slide  Lid  Wood  Cases,  with 

Ivory  or  Metal  scale  (fig.  240)  ...  6s.  6d.     0  10    6        0  12    6 

240  Circular  Pocket   Thermometer  with   Ivory   scale,   in 

leather  hinged  case,  2  inches  in  diameter      ...  0  18     6 

241  Ditto,  3  inches  in  diameter,  with  Compass  in  centre       .  150 

242  Ditto,  3  inches  in  Diameter,  with  Compass  and  Sun  Dial 

in  centre  .  1  10    0        1  16    0 



FIG.  243. 

FIG.  246. 

FiG.  249. 

FIG.  246*. 

FIG.  248. 


£    s.    d. 

1   10      0 


£    s.    d. 

243  Boxwood    Scale    Thermometer,   on    Boxwood  Stand 

(fig.  243) 076        0  10    6 

244  Ivory  Scale  Thermometer  on  Ebony  Stand,  with  glass 

shade 10s.  6d.  0  12    6 

245  Ditto,  on  Solid  Ivory  stand      ,       .       .       .  (fig.  245)    1  12    6 

246  Ivory  Mantel  Thermometers,  handsomely  engine-turned, 

and  ornamented  in  numerous  designs  (figs.  246  &246*) 

£2  10    0    3    3    0 

247  Ditto,  with  Compass  or  Sun  Dial  at  top  (fig.  247)   .       .    1  16    0 

248  Ivory  Scale  Mantel  Thermometers,  mounted  on  Ebony 

with  solid  marble  base  (as  fig.  248)  16s.,    21s.    1  10    0 

249  Marble  Mantel  Thermometer,  as  fig.  249,  Obelisk  and 

various  other  patterns  from 1  10     0 

250    Ditto    Ditto        Serpentine  Marble 



1  15    0 

£2  2s.    2  10    0  to  5    5    0 


251  8-inch   Botanical    Thermometer,    Boxwood   Scale,  in 

japanned  metal  cases,  range  of  scale  0  to  120°  or  150Q 

Enamel  Tube 036 

252  Ditto  ditto  ditto  10-inch 076 

253  Ditto  ditto  12  to  14-inch  Boxwood  Thermometers,  do.  do. 

10s.  6d.    0  12    6        0  13    6 

45,    COENHILL,   E.G.,   AND    122,    REGENT   STEEET,   W.,   LONDON.  157 

FIG.  280*. 

FIG.  291. 

FIG.  282.     FIG.  267. 

254  8-inch    Thermometers    on    Negretti    and    Zambra's 

Patent  Porcelain  Scales,  not  affected  by  damp,  &c.,  in 
japanned  metal  cases 

255  10-inch  ditto  ditto       .... 

256  12-inch  ditto  ditto       . 

257  14-inch  ditto  ditto       .... 

258  Hot-bed  Thermometer,  small  size,  for  Mushroom  Beds  . 

259  Hot-bed  Thermometer,  in  plain  metal  mounting  (fig.  259) 

260  Ditto   ditto  in    mahogany    frame,    encased    in    Brass 


261  Ditto  ditto,  with  Thermometer  on  the  Door  (fig.  261)     . 

262  Ground  Thermometer,  for  ascertaining  the  temperature 

of  the  earth  (figs.  261  and  259).     See  also  page  34 

263  Delicate  Thermometers,  for  inserting  in  the  stems  and 

flowers  of  growing  plants,  divided  on  the  stem    . 


264  8-inch  Brewers'  Thermometer,  Silvered  Metal  scales, 

in  japanned  metal  case 

265  10 -inch  ditto  ditto 

266  12-inch  ditto 

267  14-inch  ditto  ditto  (fig.  267) 

268  8-inch  Enamelled  Tubes,  in  Copper  Cases 

269  10-inch  ditto  ditto 

270  12 -inch  ditto  ditto        .... 

271  14-inch  ditto  ditto 

£    s.    d. 

FIG.  280. 

£    s.    d. 

0     5 

0     7 

0  10 
0  12 
0  10 

0  12 


0  10    0 

1  10  0 

1  10  0 

0  15  0 

0  10  6 

0  '4  6 
0  10  0 
0  10  0 
0  12  0 




FIG.  261.        FIG.  269. 

FIG.  289.        FIG.  296. 

FIG.  305. 
FIG.  298.    FIG.  300.  FIG.  286. 

271*  8-incli   Brewers'   Thermometer,   PORCELAIN  SCALES, 

£    s.    d. 

£    s. 











0  5 
0  7 
0  10 
0  12 

0  7 
0  8 
0  12 
0  14 

Negretti  and  Zambra's  Patent,  range  of  scale,  212 

japanned  metal  cases  as  fig.  267 

10-inch  ditto  ditto 

12-inch  ditto  ditto 

14-inch  ditto  ditto 

8-inch  ditto  Brewers'  Thermometers,  Patent  Porcelain 

Scales,  in  Copper  Cases  (fig.  267) 

10-inch  ditto  ditto 

12-inch  ditto  ditto 

14-inch  ditto  ditto 

Best  Mounted  Brewers'  Thermometer,  extra  stont  scales 

and  Scoop  shape,  rivetted  case,  as  fig.  280    . 
Brewers'     Thermometers,     Best     Mounted      with 

Blind  Scales,  in  Stout  Copper  cases  (figs.  280  and  280*) 
Ditto  ditto  lettered  instead  of  figured 

Brewers'  Standard  Reference  Thermometers  (fig.  282)  . 

Stout  Rivetted  Copper  Cases  at  a  slight  advance  on  above. 
Gyle  Tun  Thermometers,  according  to  length,  strong  Wood 
mountings  with  N.  and  Z.'s  Patent  Porcelain  Scales  and  enamelled  tubes. 
3ft.,  36s. ;        4ft.,  42s. ;        5ft.,  50s. ;        6ft.,  60s. 

0  12    6        0  16    0 


0  18 
0  18 

2    2 

45,    COBNHILL,    E.G.,   AND    122,    REGENT   STEEET,   W.,   LONDON.  159 

Each.  Each. 

£    s.    d.  £    s.    d. 

284  Vatting  Thermometers,  Metal  Scale  and  Wood  mountings, 

3  feet  stem      ...  1  10    0 

285  Ditto,  ditto  4  feet  do.  1  16    0 

286  Mash  Tun  Thermometers,  Patent  Porcelain  Scales  in 

strong  Metal  mountings  (fig.  286)  3ft.,  45s. ;    5ft.,  50s. ; 

287  Saccharometer   Thermometer   with    expansion    scale, 

enamelled  tube  on  stout  Metal  Mounting     ...  0  12     6 

288  Brewery  Yard  Thermometers  Registering  heat  and  cold. 

See  Nos.  287  to  288 0  15    0  to  2  10    0 

£89    Malt  Kiln  Thermometer,  stout  Oak  mount  and  Brass 

fittings  (fig.  289+)  .        • 0  10    6        0  12    6 





290  Floating  Bath  Thermometers,  for  keeping  constantly  in 

water  (fig.  290) 076 

291  Improved  form  of  ditto  ditto,  with  Porcelain  Scale'(fig.  291)  0  15    0 

292  Bath  Thermometer  (fig.  292)  Porcelain  Scale  in  strong 

Wood  mounting) 0  12    6 

293  Daury  Thermometers,  with  Ivory  and  Boxwood  Mountings  086 

294  Dairy  Thermometer  N.  and  Z.'s  Patent  Porcelain  Scales 

with  Silver  Mountings 0  12     6        0  15     0 

295  Ditto  ditto  in  Isolated  G-lass  Tube  3s.  6d.    0    5    6        076 

The  Isolated  Thermometers  are  made  entirely  !of  glass,  and  moderate  in 
price ;  they  are  easily  cleaned,  and  eminently  adapted  for  common  dairy, 
nursery,  or  culinary  purposes. 


296  Chemical   Thermometers  with   Plain  Boxwood  Scale, 

graduated  to  300°,  the  bulb  projecting  below  the  scale 

(fig.  296) 056 

297  Ditto,  with  Brass  hinge  jointed  Boxwood  scale,  to  300°  .  086 

298  Ditto,  superior  enamel  tube,  and  French  polished,  600° 

(fig.  298) 0  12    6 

299  Chemical  Thermometer,  graduated  on  stem  for  inserting 

in  the  tubulure  of  Retorts,  to  400°        ....  056 

300  Ditto                        ditto                           to  600°  (fig.  300)  076 

301  Ditto,  best  make  Enamelled  tube,  and  engine  divided     .  0  10    6 

302  Ditto  ditto,  very  finely  divided  to  half  degrees  and  tenths  0  15     0        110 

303  Standard  Thermometers  (fig.  282)  see  page  32        ..  220 

304  Thermometers  Isolated  hi  Glass  Cylinders,  for  Acids 

or  Corrosive  liquids  40°  to  300°  056 

305  Ditto,  ditto  40°  to  600°  (fig.  305)  076 

306  Thermometers  of  extreme  delicacy,  various  forms,  for 

Physical  investigation 0  10     6        0  15     0 

307  Ditto,  Negretti  and  Zambra's  patent  Self-registering 

ditto 0106        110 




FIG.  l. 

FIG.  2. 

308  THE  importance  of  ascertaining  and  watching  carefully  the  variations  of  tem- 
perature in  disease  is  now  daily  becoming  more  apparent.  Hitherto  one  of  the  great 
drawbacks  to  the  general  use  of  Thermometers  by  Medical  Men  has  been  the  fact 
that  sufficiently  portable  and  reliable  instruments  have  not  been  obtainable,  the 
bubble  of  air  used  in  Aitken's  Thermometer  being  frequently  found  to  be  shaken 
out,  and  the  instrument  disabled,  when  its  use  has  been  most  urgently  needed. 
This  difficulty  is  now  overcome  in  the  Clinical  Thermometers  invented  and 
manufactured  by  Messrs.  Fegretti  &  Zambra ; — they  are,  in  fact,  a  portable  form 
universally  adopted  in  all  parts  of  the  world.  The  important  advantage  of  this 
Clinical  Thermometer  is  the  Indestructible  Index — nothing  except  breakage  dis- 
turbing the  reliabilty  and  accuracy  of  its  indications — for  the  Column  of  Mercury 
itself  forms  the  index  (without  any  intervening  air-bubble  or  needle) — simply 
shaking  down  the  mercury  below  the  divisions  on  the  tube  after  use  at  once  adjusts 
the  Thermometer  ready  for  future  observation.  Thus  the  Practitioner  may  now 
with  the  greatest  confidence  and  convenience  carry  about  with  him  a  valuable  aid 
in  Physical  Diagnosis,  without  any  fear  whatever  of  his  Thermometer  failing  at  a 
critical  moment, — all  other  Clinical  Thermometers  being  subject  to  the  defect  of 
having  their  Indices  shaken  down  into  the  bulb  by  concussion  in  carrying  about, 
and  thus  rendered  useless. 

Holding  the  instrument  firmly,  with  a  rapid  swing  of  the  hand  and  arm  shake  or  jerk  down 
the  column  of  mercury  until  it  sinks  below  the  line  of  divisions  on  the  stem  of  the  Ther- 
mometer, as  shown  in  Fig.  1,  at  90°.  The  instrument  is  now  ready  for  use,  and  being 
applied  to  the  body  of  the  patient  for  a  sufficient  time,  will  indicate  the  maximum  tempe- 
rature by  the  position  of  the  top  of  mercury  in  the  tube,  as  seen  in  Fig.  2.  It  is  not 
requisite  that  this  Thermometer  be  read  off  whilst  in  contact  with  the  body  of  the  patient, 
for  it  may  be  removed  and  laid  aside  until  a  convenient  opportunity  occurs  for  noting  its 
indication.  These  Thermometers  are  divided  to  Fahrenheit's  scale,  each  degree  being 
subdivided  into  fifths,  or  by  the  Centigrade  scale,  sub-divided  into  tenths. 

5,    CORNHILL,   E.G.,   AND    122,    EEGENT    STREET,    W.,    LONDON. 


FIG.  309. 


I.  The  index  must  be  set  before  commencing  to  take  an  observation. 

[N.B. — The  index  is  a  portion  of  mercury  detached  from  THE  COLUMN  IN  THE  STEM 


.  1.  After  the  index  has  thus  been  set,  the  bulb  of  the  instrument  may  then  be  applied 
to  the  axilla,  or  any  part  which  is  completely  covered  ;  and,  being  retained  in  close  apposition 
with  the  surrounding  soft  parts  for  a  period  of  not  less  than  three  minutes,  the  instrument 
is  to  be  carefully  and  gently  removed,  when  the  top  of  the  index — i.e.,  the  end  furthest  from 
the  bulb — will  denote  the  maximum  temperature  during  the  period  the  instrument  has  been 
in  perfect  contact  with  the  patient. 

II.  THE  OBSERVATIONS  ought  to  be  continuous  daily,  and  regularly  taken  at  the  same 
hour  every  day  throughout  the  whole  period  of  sickness.     The  most  useful  periods  for 
observation  are — 1.  Between  7  and  9  o'clock  in  the  morning  ;  2.  At  noon;  3.  Between  5 
and  7  o'clock  in  the  evening  ;  4.  At  midnight. 

III.  In  all  observations  of  temperature,  the  Pulse  and  the  Respirations  should  be  noted 
at  the  same  time. 

The  normal  temperature  of  the  human  body,  at  complete  sheltered  parts  of  its  surface, 
amounts  to  98'5°  Fahr.,  or  a  few  tenths  more  or  less;  and  a  rising  above  99'5°  Fahr.,  or  a 
depression  below  97*3°  Fahr.,  are  sure  signs  of  some  kind  of  disease,  if  suck  increase  or 
depression  is  persistent. 

The  average  temperature  of  the  trunk  of  the  body  in  the  Tropics  is  nearly  one  degree 
higher  than  in  temperate  regions. 

The  increase  of  temperature  above  99°  Fahr.,  as  measured  by  the  Thermometer,  is  the 
best  index  of  the  amount  of  fever  present  in  any  disease. 

The  temperature  of  the  body  in  disease  is  much  more  readily  and  rapidly  influenced 
than  either  the  pulse  or  the  respiration. 

The  co-relation  of  the  pulse,  respiration  and  temperature,  is  of  the  utmost  importance 
to  be  known  in  many  diseases.  For  example,  in  Pneumonia,  if  the  mean  of  the  temperature 
is  not  above  104°  Fahr.,  and  that  of  the  pulse  is  not  above  120  in  a  minute,  and  the  mean  of 
the  respirations  not  over  40  in  the  same  time,  the  case  must  be  considered  a  slight  one  ;  and 
if  the  patient  is  otherwise  healthy  he  will  surely  begin  to  get  well  in  from  8  to  10  days, 
without  any  medical  treatment  beyond  attention  to  diet  and  rest. 

Each  disease  which  runs  a  definite  course  (e.g.,  scarlet  fever,  measles,  small-pox,  typhus 
fever,  typhoid  fever,  rheumatism,  avute  phthisis,  and  the  like,)  has  a  characteristic  and  dis- 
tinctive range  of  temperature. 

FIG.  309*. 

Printed  instructions  for  use  given  with  the  Clinical  Thermometers,  and  further  par- 
ticulars  of  their  practical  application  may  be  found  in  "  Aitken's  Science  and  Practice 
of  Medicine" 



FIG.  310*. 


310  Clinical  Thermometers,  of  large  size  for  Hospital  use, 
in  Mahogany  case 

Clinical  Thermometer,  4,  5,  'or  6-in.,  long,  straight, 
self -registering,  in  pocket  case  as  figs.  1  and  2  . 

Ditto  ditto,  with  Magnifying  Index 

Sterling  Silver  Case  for  ditto  extra  (fig.  310*)  .... 

German  Silver  Case  for  ditto     ,,        .         .         .         .         . 

Clinical  Thermometer,  curved,  in  hinged  leather  case 

Pair  of  Clinical  Thermometers,  1  straight  and  1  curved,  in 
hinged  leather  case  (fig.  309) 

Kew  Certificate  of  Clinical  Thermometer,  extra 

£    s.    d. 


£    s.    <} 


0  7 
0  10 
0-  5 
0  1 
0  10 

Clinical  Thermometers  with  Centigrade  Scales  at  same  prices  as  above  list. 



0  12    6 

FIG.  312. 

Veterinary  or  Cattle  Plague  Thermometers,  large  and 

strongly  mounted,  in  stout  Pocket  Case 
Ditto,  ditto,  in  ditto,  with  Metal  Protecting   Sheath 

(fig.  312) 0  14 

These  Thermometers  are  a  large  form  of  Negretti  &  Zambra's  Clinical 

instruments,  and  are  identical  in  their  construction  and  use. 
Disinfecting  Thermometers  ;  see  Special  Thermometer  Section. 


1851.  Prize  Medal  for  Meteorological  Instruments,  London.     1855.  "  Honourable  Mention." — Paris  Exhibition, 
The  "  Austrian  Gold  Medal."    1862.  Two  Prize  Medals,  London.    1875.  A  Prize  Medal.— Santiago,  Chili. 
1876.  Three  Prize  Medals,— Philadelphia.    1878.  A  Gold  Medal,  Paris.    The  only  Gold  Medal  awarded  for 

Meteorological  Instruments  in  the  British  Section. 
1881.  Silver  Medal,  Norwich.    1882.  Silver  Medal,  Edinburgh.    1883.  2  Gold  Medals,  1  Silver,  1  Bronze, 

Eoyal  International  Fisheries  Exhibition,  London. 

1883.  A  Gold  Medal,  Buitenzorg,  Batavia,  Java.    1884.  International  Health  Exhibition,  London, 
3  awards  and  Gold  .Medal. 


313  Rutherford's  Maximum  Thermometer,  on  Boxwood  or 

Metal  scale,  with  Steel  or  Graphite  index      056 

314  Phillip's  Maximum  Thermometer,  on  Boxwood  Scale, 

with  Air  Index       .    * 

315  Ditto  ditto,   on  Negretti  and    Zambra's    Patent 

Porcelain  or  Metal  Scale 

076        0  10    6 

0  10    6 

0  12    6 

45,    CORNHILL,    E.G.,    AND    122,    KEGENT    STREET,   W.,    LONDON.  163 

o  fl ',,,,,',,     • ,'„„„•„  ,'  ,„  ' '„  ,.',  „„•„  .„',„,.',,,,•  ,',„,'    ,  i    • 

'       1       '"' '  ' J     ----- L^»-'1  ''  '  "-^-l'".i'"'''""1"1""  Tiirnuiriiiii7^^^^ 

Jik  •  to  o    ID    70  so  40    so   60   70  eo   30  loo  "no"  iio  iso 

«          PATENT 

FIG.  317. 

Each.  Each. 

£    s.    d.         £    s.    d. 

316  Negretti       and       Zambia's       Patent       Maximum 

Thermometer,*  on  Boxwood  Scale       ....  0  10  6 

Ditto  ditto,  Patent  Solid  Porcelain  Scale   .  0  10  fi 

Ditto  ditto,  Patent  Porcelain,  or  Zinc  Scale  in 

Japanned  Metal  Case 0  10  6 

317  Ditto,  ditto,  on  Negretti  and  Zambra's  Metal  Scales 

with  Oak  mounting,  (fig.  317) 0  12     6 


o     10     20    30  ^0     50    60    70    30  J?0     100    110    /20 

^16^  ^g^ 

LONL'ON     ^         e  PATENT 

FIG.  322. 

318  Minimum  Thermometer,  Rutherford's,  on  Boxwood  or 

Metal  Scale 3s.  6d.    0    5    6        076 

319  Ditto,  ditto,  superior  mountings  0  10    6 

320  Ditto,  on  Negretti  and  Zambra's  Patent  Solid  Porcelain 

Scale 0  10     (y 

321  Minimum    Thermometer,    mounted    on    Negretti  and 

Zambra's     Patent     Porcelain     or     Zinc     Scale     in 

a  Japanned  metal  Case  .......  0  10     6 

322  Ditto    ditto,    on    Metal    Scales    with    Oak    mounting 

(fig.  322) 0  12    6 

323  Negretti  and  Zambra's  Vertical  Minimum  Thermometer, 

a  most  convenient  Window  instrument  for  exhibiting 

Present  and  Lowest  temperature 0  12    6        0  15     0 

*  This  Instrument  is  the  only  Maximum  Thermometer  that  can  be  recommended,  as  unless  it  he  broken 
it  cannot  be  put  out  of  adjustment ;  all  others  are  liable  to  become  defective  in  transit.  It  is  fully  described 
under  the  head  of  Standard  Maxima  Thermometers,  pages  36  and  38,  and  at  page  45  will  be  found 
particulars  of  the  construction  and  use  of  Minima  Thermometers. 

11  2 




FIG.  324. 


For  determining  the  greatest  cold  during  the  night  or  absence  of  the  observer- 
This  instrument  is  a  Spirit  Minimum  Thermometer,  similar  in  construction  to  No 
53,  page  45.  The  lowest  temperature  being  recorded  by  a  black  glass  index  floating 
in  the  spirit.  The  scale  is  made  of  stout  zinc,  enclosing  the  tube ;  the  figures  and 
divisions  being  boldly  marked  for  quickly  and  easily  reading  the  indications. 

(fig.  324)  Price,  3s.  6d. 

Strongly  recommended  in  all  the  leading  Horticultural  Journals  as  the  cheapest  and  best  registering 
thermometer  of  the  kind  for  garden  purposes. 

Many  hundreds  of  grosses  of  these  registering  thermometers  have  been  sold, 
giving  universal  satisfaction.     Instructions  for  use  given  with  each  instrument. 


One  of  the  most  elegant  and  ingenious  Registering  Thermometers  is  that 
invented  many  years  back  by  James  Six,  Esq.,  of  Canterbury.*  It  records  the 
highest  and  lowest  temperature  (or  heat  and  cold,  as  it  is  commonly  termed)  during 
any  given  period  of  time  in  an  exceedingly  simple  and  convenient  manner,  and  also 
at  any  moment  showing  present  temperature. 


Consists  of  a  long  cylindrical  bulb  united  to  a  smaller  tube  of  more  than  twice  its 
length,  bent  round  each  side  of  it  in  the  form  of  a  syphon,  and  ter- 
minating in  a  small  pear-shaped  bulb,  as  shown  in  the  engraving  (fig. 
325).  The  lower  portion  of  the  bent  tube  is  filled  with  Mercury  ;  and 
the  long  bulb,  the  upper  parts  of  the  tube,  and  part  of  the  small  bulb, 
with  highly-rectified  Alcohol.  In  the  tubes  will  be  found  two  steel  needles 
or  indices,  terminated  at  top  and  bottom  with  a  bead  of  glass,  to  enable 
them  to  move  with  the  least  possible  friction.  These  needles  would, 
from  their  weight,  rest  upon  the  mercury ;  but  each  has  a  fine  hair  tied 
to  its  upper  extremity  and  bent  against  the  interior  of  the  tube,  acting 
as  a  spring  with  sufficient  elasticity  to  keep  the  index  supported  in  the 
spirit  at  any  point  to  which  they  may  be  raised  in  the  tube  by  the 

The  instrument  acts  as  follows : — A  rise  of  temperature  causes  the 
spirit  in  the  long  bulb  to  expand,  and  pressing  the  mercury  down  the 
left-hand  tube  causes  it  to  rise  in  the  opposite  one,  raising  the  index 
with  it  until  the  highest  temperature  is  attained.  The  lower  end  of  the 
index  then  indicates  upon  the  engraved  scale  the  Maximum  temperature. 
As  the  temperature  falls,  the  spirit  and  the  mercury  contract,  and  in 
returning  towards  the  long  bulb  the  opposite  index  is  carried  up  by 
the  mercury  until  the  lowest  temperature  occurs,  where  it  is  left 
indicating  upon  the  scale  the  Minimum  temperature. 

FIG.  325. 

*  See  "  Philosophical  Transactions  "  for  the  years  1782  and  1790.     By  some  writers  the  name  is  spelt 
Size,  and  of  Colchester. 

45,    COENHILL,    E.G.,    AND    122,    KEGENT    STKEET,    W.,    LONDON.  165 

The  scale  on  the  right  hand  is  an  ascending  one,  and  on  the  left  descending, 
as  will  be  seen  in  our  engraving  (fig.  336).  The  thermometer  is  set  for  observation 
by  drawing  the  indices  down  to  the  surface  of  the  mercury  by  a  small  magnet,  which 
attracts  the  steel  through  the  glass,  so  that  it  is  easily  moved  up  or  down.  They 
should  be  drawn  nearly  to  the  top  of  the  tubes  when  it  is  desired  to  remove  the 
instrument,  which  should  be  carefully  carried  in  the  vertical  position ;  for  should 
it  be  inverted,  or  laid  flat,  it  may  become  put  out  of  order.  For  transmission  by 
ordinary  conveyances,  it  requires  that  attention  be  given  to  keep  it  vertical.  Six's 
Registering  Thermometers  should  be  always  hung  strictly  in  the  shade. 

These  Thermometers,  when  carefully  made  and  adjusted  to  a  standard 
thermometer,  are  recommended  as  very  convenient  for  ordinary  purposes,  where 
strict  scientific  accuracy  is  not  required. 

FIG.  333. 

FIG.  331. 

FIG.  335. 

FIG.  336. 

326  Six's  Registering  Thermometer,  8-inch  Boxwood  Scale,  £Esachd 

plain  tube       .... 

327  Ditto  ditto,        enamelled  tube    .        !        ! 

328  Ditto  ditto,        with  bevelled  edges     . 

329  Ditto  with  8-inch  Zinc  or  Boxwood  scale,  in 

Japanned  Metal  case      . 

330  Ditto  ditto,        10-inch         .'.!". 

331  Ditto  ditto,        12-inch,  Porcelain  Scale  (fig.  331) 

332  Six's    Registering    Thermometers,  with    Opal  Glass 

scales,  in  japanned  Metal  cases   (figs.  331  and  336) 

12s.  6d.,    21s.     1 

Copper  cases,  3s.  extra. 

£    s.    d. 

0  10  6 

0  10 

0  15 

1  1 

10    0        22 







&    s.    d. 

£    s.    d. 



Six's  Registering  Thermometers,  with  Opal  Glass  Scale, 

and  the  divisions  and  figures  enamelled  and  burnt  in, 

mounted  on  Oak  and  other  woods,  suited  for  Halls, 

Libraries,  Dining  rooms,  &c.  (fig.  333)  15s.,     21s.     1  10     0        220 

Six's  Thermometers,  with  NEGRETTI  AND  ZAMBIA'S 

Patent  Bulbs 25s. 

Six's    Registering    Thermometers,  Opal  Glass  scales, 

fitted    on    Bronzed     Metal    brackets     and    Oak    or 
Mahogany  board   for   suspending  outside   a  window, 

(fig.  335) 25s. 

Six's   Thermometers   with    extra   large    size   Patent 

Porcelain  or  Opal  Glass  Scale,  and  very  legible  figures 

and  divisions  (fig.  336)  and  Various  Mountings  . 

1  10    0        250 


330        3  10    0 

FIG.  337. 

337  Negretti    and    Zambra's    small    size    Patent    Maximum    and    Minimum 

Thermometer.  The  Tubes  divided  on  the  Stem,  arranged  in  a  mahogany 
case,  suited  for  travellers  to  whom  bulk  and  weight  is  an  object  (fig.  337) 
Pocket-size ...220 

338  Ditto  ditto,  larger  Standard  size,  see  also  page  51    .        .        .    2  10    0 

FIG.  339. 

339    Day  and  Night  Registering  Thermometer,  Rutherford's,* 
on  a  Boxwood  scale,  with  a  Magnet  (fig.  339) 

0  15    0        1  10    0 

too   no    m    wo    sn    sc     70     to     so     40 

FIG.  340. 

Day  and  Night  Registering  Thermometer,  with  Cylinder  Bulbs  and  enamel 
tubes  of  large  internal  diameter.  The  Maximum  Thermometer,  Negretti 
and  Zambra's  Patent  arrangement,  and  each  tube  mounted  on  a  separate 
scale,  but  joined  together  with  a  screw  in  order  that  the  Thermometers 
can  be  used  either  combined  or  alone  (fig.  340)  .  .  .  .220 

Negretti  and  Zambra's  large  sized  Maximum  and  Minimum  Sea  Coast 
Registering  Thermometers,  with  Porcelain  Scales,  as  constructed  for 
Admiral  Fitz-Boy  .........  each  220 


*  This  Thermometer  is  very  liable  to  get  out  of  order,  hence  it  is  now  but  seldom  used. 

45,   COKNHILL,    E.C.,    AND   122,    REGENT   STREET,    W.,    LONDON. 


,    FIG.  372.      FIG.  379*.    FIG.  362.        FIG.  367.           FIG.  364.        FIG.  348.  FIG.  347. 

„        ,  .    ,                                                                    Each.  Each. 

342  Oven  Thermometers  for  high  temperatures,  on  heavy    £  B.   d.  £  B.   d. 

Cast  Iron  Stand  to  equalise  the  acquired  temperature, 

range  of  scale  about  50°  to  300P  Fah 0  14    0  160 

343  Ditto,  Negretti  and  Zambra's  Patent  self -registering     .110  1  10    0 
342*  Pit  Thermometers,  (Mining)  Strongly  mounted     .        .026  0  12    0 
343*  Dairy  Thermometers,  with  Ivory   mountings,  various 

344  Beehive  Thermometers.    See  No.  235.    Boxwood  . 

345  Soap  Boilers'  Thermometers 

346  Dentists'  Thermometers,  for  Vulcanising  process  7s.  6d.    0  12    6 

347  Sugar-boiling  Thermometer,  3  to  4  feet  long,  graduated 

to  300°,  strongly  mounted      ....    (fig.  347)     1  12     0 

348  Sugar-boiling  Thermometer,  14-inch  stout  metal  scales, 

divided  from  300°F.  to  600°F.  in  stout  rivetted  Copper 
Cases  (fig.  348) 

349  Confectioners'    Thermometers,   isolated  Glass    Tubes, 

to  212°F 

350  Chemical  Manufacturers'  Thermometers,  suited  for  Acid 

or  Corrosive  liquids,  or  general  Laboratory  use.     See 
page  159,  300°  to  600°     ...  ... 

See  Nos.  293  to  295. 

076  0  10  6 
0  10  6 


0  16    0 

036        076 

0  10    6 


Each.  Each. 

£    s.    d.  £    s.    d. 

351  Confectioners'  Sugar-boiling  Thermometers,  in  Round 

Brass  Cases,  strongly  mounted,  range  of  scale  400°F. 

to  600°F 0  10    6 

352  Vinegar  Makers'  Thermometers,  various        .       .       .036       056 

353  Ditto     ditto  without  any  Metal  mountings,  as  fig.  292  .     0  10     6        0  15     0 

354  Varnish    Makers'   Thermometers,  with  strong  Metal 

mountings,  3  feet  long,  form  as  fig.  347          .     1  16     0     2     2     0        2  10     0 

355  Hay  Stack   Thermometers,  or   "Rick"   Temperature 

Tester,  7  to  8  feet  long,  strong  Iron  Mounting,  with 

N.  and  Z's.  Patent  Registering  Thermometer      .  1  10     0 

Extra  Thermometer  for  ditto 0  12     6 

356  Boiling  Point  Thermometers,  for  determining  heights 

by  observing  the  Boiling  point  of  water.     See  page  93  1  10     0 

357  Alarm  or  Valve-regulating  Thermometers,  mounted  on 

a  Mahogany  board  or  Brass  stand         .         .         .  from  220 

358  Thermostat  or  Metallic  Thermometer,  for  similar  purposes  as 

above,  an  arrangement  of  Metallic  bars  of  different  metals       made  to  order. 

359  Leslie's  Differential  Thermometers,  for  delicate  experi- 

ments on  Radiant  Heat,  &c.  (See  page  187)   .        .        .     1  10    0        220 

360  Air  Thermometers  for  ditto  ditto    .        .        .        .    0  15    0        110 

Boyle's  arrangement,  one  of  the  earliest  forms  of  Thermometer  used. 

361  Still  Thermometers  of  various  lengths  and  mountings 

figs.  379  and  347  made  to  order. 

362  Steam  Pressure  Thermometers  (or  Thermo-Pressure 

Gauge),  in  strong  Brass  case  (fig.  362)   .        .        .        .150        1  15     0 

363  Ditto  ditto  with  Hinged  Door  and  plug  for  closing  the 

boiler  when  the  Thermometer  is  not  in  use  (fig.  367)     .  220 

364  Hot  Water  Thermometers,  for  low  pressures,  small  size 

(fig.    364)    for    attaching  to   Hot    Water    Warming 

apparatus,  &c 0  18    0        140 

365  Cooking  or  Culinary  Thermometers,  of  various  forms, 

see  also  342  343  and  348 10s.  6d.     0  12    6        110 

366  Fryometer,  as  used  at  the  National  Training  School  of 

Cookery,  South  Kensington.     Copper  Mountings         .  0  16     6 

367  Vacuum  Pan  Thermometers,  stout  Brass  mounting  with 

hinged  or  Revolving  Door,  as  fig.  367     .         .        .        .220        2  10    0 

368  Hot  Air  Thermometers,  for    Turkish   Baths,  various 

forms 16s.     110150        1160 

369  Upcast  Shaft  Thermometers,  Self-Registering,  from  50° 

to  600°  enclosed  in  round  Copper  Case  ,  1  12    0 

370  Ditto       ditto,  or  Hot  Blast  Thermometer,  for  High 

temperatures  in  furnace  shafts  (fig.  372)         ...  1  10    0 

371  Registering  Air  Shaft  Thermometers,  Negretti  and 

Zambra's  Improved,  for  ditto  ditto     See  page  170          .  220 

372  Super    Heated  Steam    Thermometers,    with    Patent 

Porcelain  Scales,  in  strong  japanned  Iron  mountings 

(fig.  372) 1  10    0 

373  Ditto  ditto  ditto  smaller  size.  150 

374  Super    Heated    Steam    Thermometers,    with    Brass 

mountings,  as  figs.  362  and  367 220        2  10    0 

45,    CORNHILL,    B.C.,    AND    122,    REGENT   STREET,    W.,    LONDON.  169 

Each.  Each. 

£    s.    d.  £    s.    d. 

377  Oil  Testing  Thermometers,  for  testing  the  Heat  of 

Bearings,  the  Lubricating  quality  of  Oils,  &c.,  made 

to  Order  and  Drawings. 

378  Thermometers  for  Hot  Rollers,     ditto  ditto 

379  Salinometer  Thermometer.    See  Salinometer         .  066 
378*  Stout  Copper  Trial  Pots  for  ditto,  with  division      .  086 
379*  Disinf ecting  Thermometers,  for  Hospital,  Workhouse,  or 

Mortuary  use,  simple  form,  (fig  379°)     .         .        .   16s.     150        1  16     0 

380  Ditto  ditto,  Bent  form,  of  any  length  of  Tube  or  Scale 

to  special  Order  and  drawings. 

381  Reference  Standard  Thermometers.    See  page  158,  fig.  282, 

and  page  32     .  .         .         .         .        .        .  from  220 

382  Hydrometer  Thermometer,  with  Ivory  Scale  .  076 

383  Saccharometer  Thermometer,  with  Expansion  Scale  on 

Silvered  Metal  (fig.  348)  ......  0  14    0 

384  Incubating  Thermometers,  Low  range  on  long  Metal  Scale  98°  to  100°    036 

385  Ditto        ditto,     High  range,  Short  Metal  Scale  190°  to  210°    .        .036 

386  Ditto        ditto,    Low  range  divided  on  the  Stem  90°  to  130°    .         .026 

387  Ditto        ditto,     High  range  divided  on  the  Stem  150°  to  220°         .036 

388  Ditto        ditto,     8-inch  Metal  Scale  Thermometer,  in  japanned  case    026 

389  Ditto        ditto,     10-inch  ditto        ditto,        without  case  .         .         .036 

390  Ditto        ditto,     Small  Bent  Tube  in  Metal  Mounting       .         .         .046 

391  Incubating  Thermometers,  extra  sensitive,  for  Experimental  purposes. 

Made  to  order. 

392  Thermometers,  Extreme  Low  range,  for  Refrigerating  Chambers,  ditto  ditto. 
391*  Petroleum  Testing  Thermometers  (fig.  391*) 0  10    6 

393  The  Elaeometer,  for  testing  Olive  oil  or  Oil  of  Almonds.    The  O  at  the  bottom 
of  the  scale  is  the  point  at  which  this  instrument  floats  in  Pure  Oil  of  Poppy  Seeds. 
The  point  at  which  it  floats  in  Pure  Olive  Oil  is  made  the  50th  degree,  and  the 
space  between  these  two  points   is   divided  into  50  equal  parts  and  numbered 
accordingly.     It  floats  at  38  or  38|Q  in  Pure  Oil  of  Almonds.  Price,  5s.  6d. 


Fahrenheit.  Centigrade.  Eeaumur. 

4-212°  +100°'0  +  80°'0 

100'  37-8  30-2 

50'  10-  8-0 

32-  0-0  0-0 

-i-10-  -12-2  -9-8 

0-  -17-8  -14-2 

-10-  -23-3  -18-6 

-20-  -28-9  -23-1 

-50-  -45-5  -36-4 

-70-  -56-6  -45-3 

Value  of  one  degree  of  these  Scales. 

1°  Fahrenheit  =  £  Centigrade  =  %  Reaumur 
1°  Centigrade  =  1-8  Fahrenheit  =  0'8  Reaumur 
1°  Reaumur  =  2-25  Fahrenheit  =  1-25  Centigrade 

Elementary  Meteorology,  B.  H.  SCOTT,  F.R.S. 



FIG    395.  FIG-.  395.  FIG.  396. 

395  Paraffin  Testing  Apparatus,  with  Thermometer  and  Spirit  Lamp    £  B.    a. 

(fig.  395) 0  15    6 

Fig.  395  shows  a  simple  Apparatus  for  testing  Petroleum  to  ascertain  the 
temperature  at  which  it  gives  off  inflammable  vapour.  It  consists  of  a  sheet-iron 
vessel  to  hold  the  Petroleum  to  be  tested ;  this  is  placed  in  an  outer  vessel  to  hold 
water  (somewhat  in  the  manner  of  an  ordinary  gluepot)  with  a  metal  support,  so 
arranged  that  the  water  can  be  gradually  heated  by  a  Spirit  {Lamp,  and  the 
temperature  of  the  Petroleum  conveniently  observed  by  a  reliable  Thermometer. 

396  Petroleum  Testing  Apparatus,  for  testing  the  Flashing  Point  of  Illuminating 

Oils.      Sir  Frederick' Abel's      Government  Pattern,   as    supplied  to  the 
Government  Inspectors  under  the  Petroleum  Act,  1879. 

Complete  in  Box,  for  use  with  Oil  or  Gas  only  (fig.  396)  6  10    0 

Do.  do.,  arranged  for  use  with  either  Oil  or  Gas     .  7  10     0 

Including  Verification  at  Standard  Department. 
An  Act  to  continue  and  amend  the  Petroleum  Act,  1871.     [August  llth,  1879.] 

1.  This  Act  may  be  cited  as  the  Petroleum  Act,  1879. 

This  Act  shall  be  construed  as  one  with  the  Petroleum,  1871,  and  together  with  that 
Act  may  be  cited  as  the  Petroleum  Acts,  1871  and  1879. 

2.  Whereas  by  the  Petroleum  Act,  1871,  it  is  enacted  that  the  term  "  petroleum  to 
which  this  Act  applies  "  means  such  of  the  petroleum  denned  by  that  Act  as,  when  tested 
in  manner  set  forth  in  Schedule   One  to  the  Act,  gives  off  an  inflammable  vapour  at  a 
temperature  of  less  than  one  hundred   degrees  of    Fahrenheit's   thermometer,   and  it  is 
expedient  to  alter  the  said  test :  Be  it  therefore  enacted  that — 

In  the  Petroleum  Act,  1871,  the  term  "  petroleum  to  which  the  Act  applies  "  shall  mean 
such  of  the  petroleum  defined  by  section  three  of  that  Act  as,  when  tested  in  manner  set 
forth  in  Schedule  One  to  this  Act,  gives  off  an  inflammable  vapour  at  a  temperature  of 
less  than  seventy-three  degrees  of  Fahrenheit's  thermometer. 

Every  reference  in  the  Petroleum  Act,  1871,  to  Schedule  One  to  that  Act  shall  be 
construed  to  refer  to  Schedule  One  to  this  Act. 

Petroleum  Act  of  1879  giving  description  of  the  above  Apparatus  and  instructions 
for  using  it,  price  per  post,  6d. 

45,  COENHILL,  E.G.,  AND  122,  REGENT  STREET,  W.,  LONDON. 


FIG.  398. 

FIG.  399. 

FIG.  400*. 

FIG.  400.    FIG.  402. 


For  ascertaining  Underground  Temperature,  the  Temperature  of  Mines,  Thermal 
or  Boiling  Springs,  Air  Shafts,  Atmospheric  Temperature,  &c.,  &c. 

397  The  above  engravings  represent  various  forms  of  Negretti  and  Zambia's 
Patent  Self-Registering  Thermometers,  each  adapted  to  a  special  purpose ;  these 
can  be  made  available  in  many  other  ways  not  here  specified.  The  principle  on 
which  these  instruments  is  constructed,  and  the  ^manner  of  using  them,  are  fully 
set  forth  on  pages  42  and  43. 

Particular  instructions  are  supplied  with  each  Thermometer. 
Fig.  398  represents  a  Brewer's  or  Drying  Room  Self-Registering  Thermometer, 
by  which  accurate  temperatures  may  be  ascertained  in  positions  inconvenient 
of  access,  or  where  Steam,  Heat,  or  Darkness  render  the  true  readings  of  an 
ordinary  Brewer's  Thermometer  almost  impossible  to  be  obtained. 

Price  in  Stout  Copper  Case,  £110 

Fig.  399  shows  another  form  of  the  Thermometer  divided  on  its  stem, 
arranged  in  a  Glass  Sheath  mounted  on  a  Mahogany  Board  or  Metal  Plate, 
for  ascertaining  temperatures  in  Hot  Air  or  Drying  Chambers,  Baths, 
Ovens,  &c.,  &c.,  serving  as  a  check  on  temperatures  during  absence ;  or,  as 
described  pages.43  and  46,  as  a  Marine  Atmospheric  Maximum  Thermometer. 

Price,  £110 




400  Fig.  400  and  fig.  400*  are  other  arrangements  of  this  Thermometer,  made  by 

Negretti  and  Zambra  under  special  instructions  from  Professor  Everett,  for 
the  Committee  of  the  British  Association  on  Underground  Temperatures, 

401  Fig.  401  is  the  Thermometer,  enclosed  in  a  Glass  Tube  or  Sheath,  fitting  into 

a  hinged  Copper  Protecting  Case  ("Well  Thermometer),  as  seen  in  fig.  400*. 

Price,  £1  10     0 

402  Fig.  402  is  a  Thermometer  of  very  Slow  Action  for  taking  direct  Earth 

Temperatures,  The  bulb  of  this  Thermometer  is  shown  in  its  Glass  Sheath 
surrounded  by  a  good  non-conducting  substance  as  suggested  by  Professor 
Everett.  The  Thermometer  being  lowered  down  to  the  desired  depth  by  a 
cord,  is  allowed  to  remain  a  considerable  time  in  the  earth  so  as  to  attain 
the  existing  Temperature.  It  is  then  withdrawn  quickly,  and  the  reading 
noted,  the  non-conductor  around  the  Bulb  preventing  any  rapid  change 
taking  place  for  a  sufficient  time  to  ensure  accuracy.  Price,  £0  18  6 

See  also  pages  35  and  43. 

The  Range  of  Scale  of  these  Maximum  Thermometers  can  be  varied  to  suit  the 
requirements  of  the  experiments  to  be  carried  out. 

At  the  meeting  of  the  British  Association  in  1872  (Brighton),  Prof.  Phillips  when  speaking  on  the 
subject  of  the  use  of  his  own  form  of  Thermometer  for  ascertaining  underground  temperatures,  said> 
"  There  would  be  difficulty  in  using  such  instruments  where  the  light  was  bad,  and  he  thought  the 
instrument  exhibited  by  Prot'.  Everett  (Negretti's  Vertical  Thermometer;  was  better  adapted  to  the 
purposes  of  the  Committee." 

Beneath  the  surface  of  the  Earth  the  Temperature  increases  at  the  rate  of  1° 
Fah.  for  every  sixty  feet.  Another  authority  states  it  1°  Fah.  for  every  forty-nine 
feet.  The  temperature  for  the  first  sixty  feet  is  influenced  by  the  Seasons. 

In  deep  caverns,  the  effect  of  the  great  heat  of  summer  has  been  only  felt  at 
mid-winter,  and  vice-versa,  the  cold  of  winter  only  reaches  them  at  mid-summer. 

The  subjoined  list  of  Temperatures  compiled  from  various  reliable  authorities 
is  inserted  as  well  illustrating  the  above  observations. 

Artesian  Well,  Hanwell,  290  ft.  deep,  55  9. 
Grotto  del  Cane,  Italy.  68°. 
Earth  Yokutsk,  50  ft.  deep,  18°. 
Hecla  Earth  at  Summit,  153°. 
Geyser  Springs,  Iceland,  179°. 
Thermal  Spring,  Tajurah  and  Shoa,  152°. 
Thermal  Spring,  Island  of  Lucon,  174°. 
Volcanic  Mud,  Jorullo,  South  America,  203°. 
Ournastok  Spring,  Greenland,  103°. 
Comagillas,  Mexican  Springs,  205°. 
Eaux  Bonnes,  Pyrenees,  89°. 
Aix-la-Chapelle  Spring, 

Maximum  Temperature.  180°. 
Aix-la-Chapelle  Spring,  Spa,  143°. 
Baden  Baden  Springs, 

Maximum  Temperature,  157°. 

Bagneres-de-Bigore  Spring,  123°. 

Mariana  Springs,  South  America,  138°. 

Wiesbaden  Spa,  149°. 

San  Germano  Bath,  Naples,  181°. 

Buxton  Spring,  82°. 

Matlock  Spring,  66°. 

Bristol  Spa,  66°. 

King's  Bath,  Bath,  114°. 

Hot  Pump,  Bath,  116Q. 

Bath  Springs,  Maximum  Temperature  117°. 

supposed  depth,  3,350  ft. 
Monkwearmouth  Mine,  1,500  ft.  deep,  72°. 
Consol  Mine,  Cornwall,  1,740  ft.  deep,  93°. 
Cumberland  Coal  Mine,  600  ft.  deep,  66°. 
Salt  Mine,  Cracow,  730ft.  deep,  509. 
Guanaxato  Mines,  1,700  ft.  deep,  999. 

On  page  48  of  Mr.  Scott's  Book  on  Elementary  Meteorology  will  be  found  a  Chronoisothermal  Diagram 
representing  the  Monthly  Mean  Temperature  at  Greenwich  for  every  hour  of  the  day  through  the  range  of 
years  1849  to  1868.  "  This  diagram  was  devised  by  M.  Leon  Lalanne— it  exhibits  many  most  interesting 
facts  in  connection  with  the  climate  of  London,  amongst  others,  that  the  highest  mean  temperature  (70) 
only  occurs  in  the  latter  part  of  July  and  between  one  o'clock  and  half-past  three  p.m.,  and  the  lowest 
mean  temperature  (38)  is  observed  during  the  night-time  from  about  January  5th,  to  March  20th. 

Also  it  will  be  seen  that  the  coldest  time  in  summer  is  from  three  to  five  in  the  morning,  while  in 
winter  there  is  not  much  change  between  four  in  the  afternoon  and  eleven  in  the  morning.  It  will  be  also 
noticed  how  much  colder  the  Spring  equinox  is  than  the  Autumnal,  for  on  April  1st  the  temperature 
ranges  from  40°  to  50°  F.,  while  on  October  1st  the  range  is  from  50°  to  61°  F." 

t  Prof.  Everett,  D.L.C.,  of  Belfast. 

45,    CORNHILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,    LONDON. 






FIG,  407. 

FIG.  408. 

FIG.  404. 

FIG.  406. 

Board  of  Trade  Marine  Thermometer,  the  scale  divided  on  its  stem, 


and  mounted  on  Negretti  and  Zambra's  PATENT  PORCELAIN  SCALES,   £  s.  d. 

in  japanned  Metal  Case 0  10  6 

ditto  in  COPPER  CASE  (fig.  404)  0  12  6 

1  10  0 

Board  of  Trade  Marine  Thermometer,  in  round  Copper  case  .  .  1  10 
Johnson's  Registering  Metallic  Marine  Thermometer.  The  indications  are 
obtained  by  the  varying  expansion  of  brass  and  steel  bars  acting  upon  an 
index  on  the  principle  of  the  Thermostat  (fig.  401)  .  .  .  550 
For  description  see  N.  and  Z.'s  Treatise  on  Meteorological  Instruments. 

407  Deep  Sea  Sounding  Thermometers,  Self-Registering,  the  original  double  tube 

principle,  as  invented  by  Negretti  and  Zambra,  specially  constructed  for 
and  supplied  to  the  Board  of  Trade  and  Admiralty  (fig.  407).  Warranted 
to  stand  a  pressure  of  450  atmospheres 2  10  0 

Many  have  been  the  contrivances  for  obtaining  correct  deep  sea  indications.  Thermometers  and 
machines  of  various  sorts  have  been  suggested,  adopted,  and  eventually  abandoned  as  only  approximate 
instruments.  The  principal  reason  for  such  instruments  failing  to  give  correct  or  reliable  indications  has 
been  that  the  weight  or  pressure  at  great  depths  has  interfered  with  the  correct  reading  of  the  Instrument. 
Thermometers  have  been  enclosed  in  strong,  water-tight  cases  to  resist  the  pressure ;  but  this  contrivance 
has  only  had  the  tendency  to  retard  the  action,  so  much  as  to  throw  a  doubt  on  the  indications  obtained 
by  the  instrument  so  constructed. 

408  Negretti  and  Zambra's  Small  Deep  Sea  Sounding  Thermometer,  Dr.  Miller's 

pattern  in  Copper  Case  (as  fig.  403).  Price  £2  10s.     £3  3e. 

The  Deep  Sea  Sounding  Thermometers  (Nos.  406,  407  and  408)  having  all  been 
found  defective  in  their  indications,  their  use  is  not  recommended  for  reasons 
stated  in  pages  60  to  70. 



FIG.  414.  FIG.  415. 


FIG.  414*. 

409  The  almost  daily  occurrence  of  frightful  accidents  from  the  explosion  of 
steam  boilers  calls  for  the  utmost  vigilance  and  care  from  owners  and  employers  of 
steam  power.  One  of  the  most  important  precautions  is  that  of  having  accurate  and 
reliable  gauges.  Too  much  stress  cannot  be  laid  upon  this  point,  for  if,  from  motives 
of  false  economy,  cheap  and  carelessly  made  gauges  are  used,  their  indications  can 
never  be  depended  upon,  and  their  use  may  lead  to  fatal  and  costly  results.  It  has  fre- 
quently come  under  the  notice  of  Messrs.  Negretti  and  Zambra  that  Steam  Gauges 
have  been  supplied  or  repaired  by  persons  without  the  slightest  knowledge  of  their 
construction,  or  having  any  means  of  proving  or  testing ;  consequently  they  have 
been  found  fearfully  in  error,  and  worse  than  useless  because  unsafe. 

410  Steam  Gauges,  Mercurial,  from  10  to  140  Ibs.,  with  union  joint  at    £ 

either  side  of  the  frame,  in  polished  Mahogany  frame   .        .        .2 

411  Ditto,        ditto,  Brass  ditto    3 

412  Thermometric  Pressure  Gauge,  for  showing  the  pressure  of  Steam 

by  taking  its  temperature  (fig.  372),  Iron  mountings       .         .         .1 

413  Ditto        ditto,  Brass  mountings  (figs.  362  and  367)     2 

414  Ditto  ditto,        ditto  with  Bent  tubes,  as  figs.  409  and  409*, 

screw  flanges  and  stuffing  boxes,  &c.,  for  high  pressures          from     330 

415  Angle  Thermometers,  for    Yacuum  Sugar  Pans,  Brass  Mounted 

(fig.  415) 1  16    0 

416  Thermometric  Pressure  Gauges  with  Temperature  and  Pressure 

Scales  made  of  any  length  to  order  or  drawings,  with  either  English 
or  French  divisions. 


45,    CORNHILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,     LONDON. 


417  Negretti  and  Zambra's  Saturometre  or  Thermometrical  Salinometer  for 
determining  the  amount  of  Salt  held  in  solution  in  the  water  of  Marine  Boilers. 

It  is  well  known  that  pure  water  boils  at  212°  Fahr.  at  the  level  of  the  sea,  and 
if  water  is  impregnated  with  salt,  the  point  of  ebullition  is  materially  raised ;  hence 
the  water  in  a  marine  boiler  can  be  accurately  tested  as  to  its  saline  properties  by 
observing  at  what  temperature  the  ebullition  is  taking  place  within  the  boiler.  The 
apparatus  consists  of  a  metal  reservoir  attached  to  the  boiler  by  a  stopcock,  R,  and 
union  joint,  B  ;  this  reservoir  carries  a  thermometer.  T,  whose  bulb,  A,  reaches  nearly 
to  the  bottom  of  the  chamber ;  the  graduations  on  the  scale  commence  at  212°,  the 
boiling  point  of  pure  water.  At  the  bottom  of  the  reservoir  is  an  outlet  tap,  S,  and 
there  is  also  a  tap,  X,  inserted  a  little  above  the  bottom  of  the  reservoir,  with  a  tube 
connected  with  it  reaching  nearly  to  the  top  of  the  interior  of  the  reservoir. 

The  apparatus  is  used  as  follows :  the  reservoir  having  been  emptied  by  the 
tap  S,  it  should  be  closed,  and  the  taps  R  and  X  opened ;  the  water  from  the  boiler 
will  then  flow  into  the  chamber  A,  partly  fill  it,  and  pass  out  by  the  pipe  and  tap  X. 
After  the  water  has  been  allowed  to  escape  for  a  few  seconds,  the  thermometer  is  to 
be  examined,  and  according  to  the  temperature  indicated  so  will  be  the  specific 
gravity  of  the  water  in  the  boiler,  or,  in  other  words,  the  percentage  of  salt  dis- 
solved in  it.  This  fact  is  quickly  and  conveniently  ascertained  by  simply  opening 
three  taps  and  reading  the  thermometer  (fig.  416)  .  .  .  .  £440 

Our  table  in  connection  with  the  description  and  use  of  Salinometers  (page  189) 
will  give  the  relative  degrees  of  Saltness  and  Temperature. 

Messrs.  Negretti  and  Zambra  very  strongly  advise  the  use  of  the  Thermonietric 
Pressure  Gauges  (No.  409)  in  conjunction  with  the  Mercurial  and  Spring  Gauges 
as  a  comparative  and  precautionary  measure  of  safety.  When  steam  is  generated 
and  confined  in  a  boiler,  the  pressure  upon  the  boiling  water  may  be  twice  or  thrice 
that  of  the  atmosphere.  Experimentally  it  has  been  found,  that  if  the  pressure  in 
the  boiler  be  251bs.  on  the  square  inch,  the  temperature  of  the  boiling  water,  and  of 
the  steam  likewise,  is  raised  to  241° ;  and  under  the  exhausted  receiver  of  an  air- 
pump,  water  will  boil  at  185°,  when  the  pressure  is  reduced  to  17  inches  of  mercury. 
The  following  table,  compiled  by  Dr.  A.  S.  Taylor,  gives  the  relative  temperatures 
and  pressures  up  to  12  atmospheres  or  180  Ibs.  pressure. 

Water  boils.     Barometer  30  inches. 
320  degrees  Fahr.     6    Atmospheres. 
327  6'5 

Water  boils.     Barometer  30  inches. 

212  degrees  Fahr.     1     Atmosphere. 

234  „  1-5 

251  „  2  „  332  7  '„ 

267  „  2-5        „  337  7'5        „ 

275  „  3  „  342  8 

285  „  3-5         „  „ 

295  „  4  .,  359  10 

300  „  4-5        „  368  11 

307  „  5  „  374  12 

315  „  5-5         „ 

ON  COMBINED  STEAM.    By  the  Hon.  J.  WETHERED. 

"  In  its  passage  through  the  super-heating  apparatus  a  portion  of  steam  is  raised  by  the 
waste  heat  to  a  temperature  of  500°  or  600°  Fahrenheit.  The  heat  thus  arrested  is  conveyed 
to  and  utilised  in  the  cylinders  by  its  action  on  the  other  portion  of  the  steam  from  the 
boiler,  which  is  more  or  less  saturated,  according  to  circumstances.  The  combined  steam  is 
used  in  the  cylinder  at  from  300°  to  450°  Fahrenheit,  at  which  steam  is  generally  employed, 
The  effect  of  using  the  two  kinds  of  steam  is,  that  the  super-heated  steam  yields  a  portion  of 
its  excess  of  temperature  to  the  ordinary  steam,  converting  the  vesicular  water  which  it 
always  contains  into  steam,  and  expanding  it  several  hundred-fold  ;  whilst  at  the  same  time, 
the  ordinary  steam  yields  a  portion  of  its  excess  of  moisture,  converting  the  steam  gas  into 
a  highly  rarefied  elastic  vapour — in  other  words,  into  pure  steam  at  a  high  temperature." 



418  HYDROMETERS,  or  Areometers,  are  instruments  constructed  to  determine  the 
specific  gravity  of  fluids.  Their  use  has  been  traced  back  to  a  date  about  300 
years  before  Christ,  the  invention  being  ascribed  to  Archimedes,  the  Sicilian 
philosopher.  Their  action  is  dependent  upon  the  law  "  that  a  body  immersed  in 
any  liquid  sustains  a  pressure  from  below  upwards  equal  to  the  weight  of  the 
volume  of  liquid  displaced  by  such  body." 

First  on  our  list  of  Hydrometers  we  place  those  showing  Specific  Gravity, 
because  all  other  Hydrometer  scales  are  referable  to  it ;  and  as  the  figures 
indicated  are  absolute  and  definite  quantities,  or  values  without  possibility  of 
dispute,  it  is  the  best  both  for  scientific  and  manufacturing  purposes. 

The  Specific  Gravity  of  Fluids  may  simply  be  described  in  a  few  words. 

A  very  light  glass  flask  is  accurately  adjusted  and  stoppered  to  hold 
exactly  1,000  grains  of  pure  distilled  water  at  a  temperature  of  60°  Fahrenheit. 
If  this  flask  be  filled  with  highly  rectified  asther,  and  then  carefully  weighed  in 
a  delicate  balance,  it  will  be  found  that  the  flask  instead  of  holding  1,000 
grains  will  only  weigh  say  713  or  715  grains  at  60  degrees  of  temperature. 
This  is  the  specific  gravity  of  pure  a9ther,  or  as  written  in  chemical  language, 
0*713  or  0*715.  On  the  contrary,  if  the  flask  be  filled  with  concentrated  sul- 
phuric acid  it  will  be  found  to  hold  1842  or  1845  graine,  or  specific  gravity, 
1-842  or  1*845,  at  60  degrees  temperature.  In  these  readings  water  is  repre- 
sented by  one  thousand,  I'OOO. 

All  other  fluids  (save  Mercury)  will  be  found  to  be  of  intermediate  specific 
gravity,  say  between  600  and  2*000. 

Our  list  embraces  the  whole  of  the  Hydrometers  in  use  in  the  United 
Kingdom  and  most  of  the  Foreign  instruments.  The  comparative  value  of 
these  may  be  ascertained  by  reference  to  a  valuable  series  of  carefully  compiled 
tables  described  at  the  end  of  Hydrometer  Section. 

As  a  rule  all  Hydrometers  made  in  England  are  adjusted  to  a  temperature 
of  60°  Fahrenheit,  but  if  they  are  required  for  use  in  the  East  or  West  Indies, 
they  must  be  specially  adjusted  at  84°  Fahrenheit,  and  should  be  ordered 

45,    COKNHILL;    E.C  ,    AND    122,    BEGENT   STREET,   W.,   LONDON. 


FIG.  419 

FIG. 481. 

FIG.  424. 

FIG.  423. 

FIG.  436. 

FIG.  420. 

£    s.    d. 

£    s.    d. 

419  Hydrometer  from  700  to  1-000  for  Specific  Gravities 

lighter  than  water  (fig.  419) 066 

420  Hydrometer  from  1-000  to  1-850  or  2-000,  for  fluids 

heavier  than  water  (fig.  442) 066 

421  Beaume's  Hydrometer  '0  to  -70,  for  fluids  lighter  than 

water 050 

422  Ditto          Hydrometer,     '0     to     *40,    for     cane-juice 

and  similar  fluids  heavier  than  water  (fig.  422)     .  050 

423  Beaume's  Saccharometer,  Brass  Gilt,  for  sugar  boiling, 

range  '0,  '40 176 

Beaume's  Hydrometers  are  used  extensively  in  England  as  well  as  in  France, 
and  are  applicable  for  testing  all  kinds  of  liquids. 

There  are  two  distinct  instruments,  one  for  fluids  lighter  than  water,  and  the 
other  for  fluids  heavier  than  water. 

The    latter    is    for    distinction    called    the    Acidometer    or    Saccharometer 
(pvse-acide  or  pese-sirop),  the  former  the  Spirit  Hydrometer  (pese-espritj . 



FIG.  425*. 

FIG.  425. 

£    s. 

424  Government  Proof  Hydrometer,  Glass,  showing  percentages  of  proof 

spirit  from  60  over  proof  to  40  under  proof  (fig.  397)     .        .        .056 

425  Ditto  ditto  Hydrometer,  Glass,  in  mahogany  box  with  Thermometer 

(fig.  398)  with  Printed  instructions  for  use 0  15     0 

426  Ditto  ditto,  with  Ivory  sliding  Computing  Scale      .         .110 
427     Sikes'*  Hydrometer  is  the  instrument  used  by  the  government  officers  in 

the  collection  of  the  spirit  revenue  in  the  United  Kingdom.  It  is  made  entirely  of 
metal,  usually  strongly  gilt  to  prevent  corrosion. 

It  consists  of  a  globular  float  with  an  upper  and  lower  stem.  The  upper  stem 
is  flattened  and  divided  into  ten  parts,  numbered  1,  2,  3,  &c.  These  are  again  sub- 
divided into  five  parts. 

The  lower  stem  is  tapering,  and  terminating  by  a  pear-shaped  bulb.  There  are 
nine  weights  numbered  from  10  to  90,  each  weight  being  pierced  in  the  centre,  so 
that  it  can  be  placed  on  the  conical  stem  at  the  smaller  end  and  slid  down  towards 
the  bulb  until  it  becomes  securely  fastened. 

428.  Sikes'  Hydrometer  is  adjusted  to  spirit  Specific  Gravity  -825  at  60Q  Fahr., 
this  being  considered  Standard  Alcohol.  In  this  spirit  the  instrument  floats  at  the 
first  division  0  on  the  stem  without  a  weight.  In  weaker  spirit,  having  a  greater 
density,  the  Hydrometer  will  not  sink  so  low,  and  should  the  density  be  greater, 
one  of  the  weights  must  be  added  to  cause  the  entire  immersion  of  the  bulb  of  the 

Each  weight  represents  so  many  principal  divisions  of  the  stem.  Thus  the 
heaviest  weight,  marked  90,  is  equal  to  ninety  divisions  of  the  stem,  and  the  instru- 
ment with  this  weight  attached  floats  at  0  in  distilled  water. 

Each  principal  division  on  the  stem  being  divided  into  five,  the  Hydrometer 
has  a  range  of  500  degrees  between  alcohol,  sp.  gr.  '825  and  water. 

On  one  side  of  the  upper  stem,  near  to  the  division  1,  will  be  found  a  line,  at 
which  the  instrument  will  float  with  the  weight  60  attached  in  spirit  exactly  of  the 
strength  of  proof  at  a  temperature  of  51°  Fahr.,  and  if  the  square  weight  (sent  with 
the  instrument)  be  placed  on  the  top  of  the  stem,  the  weight  60  still  being  attached 
to  the  lower  stem,  the  instrument  will  float  at  the  side  line  in  distilled  water  of  the 
same  temperature.  This  square  weight  being  precisely  one-twelfth  part  of  the  total 
weight  of  the  hydrometer  and  weight  60,  the  above  indication  is  in  conformity 
with  the  definition  of  proof  spirit  stated  in  the  act  of  parliament,  "  Proof  spirit 
to  weigh  at  51°  temperature  exactly  twelve-thirteenth  parts  of  an  equal  bulk  of 
distilled  water." 

In  using  Sikes'  Hydrometer,  it  is  immersed  in  the  spirit  and  pressed  down 
to  0  until  the  whole  of  the  divided  stem  be  wet.  The  amount  of  force  required  to 

*  We  have  consulted  several  authorities  for  the  correct  spelling  of  this  name  ;  Dr.  Tire  and  Professor 
Redwood  spell  it  Sikes.  An  act  of  parliament,  26th  June,  1858,  18  and  19  Viet.,  has  Sykes— many  writers 
adopt  this.  The  same  difference  occurs  with  the  name  of  the  inventor  of  a  Maximum  and  Minimum 
Registering  Thermometer— Six  or  Sixe.  In  both  cases  there  appears  to  be  some  doubt  which  is  correct. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  429.  FIG.  429*. 

sink  it  will  determine  the  selection  of  the  requisite  weight  to  be  attached  to  the 
lower  stem.  Again  immerse  the  hydrometer  in  the  spirit,  and  allow  it  to  float 
freely  and  settle,  and  then  keeping  the  eye  in  a  line  with  the  surface  of  the  spirit, 
notice  the  division  cut  by  the  surface  as  seen  from  below.  The  number  indicated 
by  the  stem  is  added  to  the  numbers  of  the  weight,  and  the  sum  of  these,  together 
with  temperature  of  the  spirit  (which  should  be  very  carefully  noted)  will,  by 
reference  to  a  Book  of  Tables  accompanying  the  instrument,  give  the  required 
strength  per  cent,  of  the  spirit  under  test. 

The  strength  is  expressed  in  numbers  denoting  the  excess  or  deficiency  per 
cent,  of  proof  spirit  in  any  sample,  and  the  number  itself  having  its  decimal  point 
removed  two  places  to  the  left,  becomes  a  factor,  whereby  the  gauged  contents  of 
a  cask  of  such  spirit  being  multiplied,  and  the  product  being  added  to  the  gauged 
contents  if  over  proof,  or  deducted  from  it  if  under  proof,  the  result  will  be  the 
actual  quantity  of  proof  spirit  contained  in  such  vessel. 

The  commercial  term  above  or  below  proof  is  partly  derived  from  the  govern- 
ment having  fixed  a  certain  strength  of  spirit  as  mentioned  above  as  Proof  Spirit 
by  which  the  strength  of  all  spirit  is  comparable.  It  is  also  said  that  the  term 
proof  is  derived  from  an  ancient  method  of  testing  the  strength  of  spirit  by  pouring 
the  sample  over  gunpowder  in  a  metal  cup  and  then  setting  fire  to  the  spirit ;  if, 
when  the  spirit  had  burnt  away,  the  powder  exploded,  the  spirit  was  said  to  be  over 
proof;  if ,  on  the  other  hand,  the  gunpowder  did  not  ignite,  owing  to  the  large 
portion  of  water  left  behind,  it  was  said  to  be  under  proof. 

The  weakest  spirit  capable  of  firing  gunpowder  by  this  method  was  called  proof 
spirit,  but  it  required  a  spirit  of  nearly  the  strength  of  what  is  now  called  rectified 
spirit  to  stand  this  test. 

The  Standard  Proof  Spirit  of  the  excise  is  defined  by  law  (56  Geo.  III.  cap. 
140)  to  be  "  that  which  at  a  temperature  of  51°  Fahrenheit's  Thermometer,  weighs 
exactly  twelve-thirteenth  parts  of  an  equal  measure  of  distilled  water" 

This  will  have  a  specific  gravity  of  '923  at  51°  Fahrenheit,  or  about  -920  at  60° 

The  Standard  Alcohol  of  the  Excise  is  spirit  of  the  specific  gravity  '825  at  60Q 
Fahrenheit.  By  "  Spirit  60  degrees  over  proof  "  is  understood  a  spirit  100  measures 
of  which  added  to  60  measures  of  water  will  form  Standard  Proof  Spirit,  specific 
gravity  '920. 

By  "  Spirit  10  degrees  under  proof "  is  understood  a  spirit  100  measures  of 
which  mixed  with  10  measures  of  standard  alcohol,  specific  gravity  '825,  will  form 
Standard  Proof  Spirit. 

NOTE.— We  are  indebted  to  Professor  Bed  wood  for  most  of  the  figures  given  in  connection  with 
Sikes'  Hydrometer.  The  British  Pharmacopoeia  of  1864  orders  that  the  Specific  Gravity  of  liquids  is  to  be 
taken  at  a  temperature  of  60  degrees  by  Fahrenheit's  Thermometer,  and  gives  the  Specific  Gravity  of 
absolute  Alcohol  as  0795,  Rectified  Spirit  (Spiritus  Eectificatus)  as  0'838.  and  Proof  Spirit  ( Spiritus  Tenuior) 
as  0-920,  at  a  temperature  of  60  degrees  Fahrenheit. 

N   2 



5      5 

0    7 
0  10 

0  15 

1  10 

429  Sikes1  Hydrometer,  Double  Gilt  Metal,  with  silver  soldered  joints,         Each. 

as  used  by  the  Excise  and  Customs,  with  weights,  enamel  tube   £    s.     a. 
Thermometer,  Test  Glass,  and  Book  of  Tables  (figs.  429  and  429*)    400 

430  Ditto  ditto,  with  Comparative  Rules     4  10     0 

431  Sikes'  Hydrometer  Standard,   Gilt  Metal,  5-inch  range   on   stem, 

divided  to  l-10ths 

Book  of  Tables  for  use  with  Sikes'  Hydrometer  to  80°  Fahr     . 
Ditto  ditto  ditto  to  100°  Fahr.     . 

432  Sikes'  Pocket  Hydrometer  in  German  Silver      .... 

433  Ditto  with  Thermometer,  jar  and  case 

434  Dicas's  and  Allan's  Hydrometers  are  very  similar  in  construction 

to  Sikes'  instrument,  but  are  now  very  rarely  used. 

Saccharometer  for  Brewer's  use.     Shows  the  weight  of  wort  per  barrel  heavier 
than  water.     Thus  36  gallons  of  water  weighs  360  Ibs.,  but  36  gallons  of  wort  of 
specific  gra,vity  1'050,  weighs  18  Ibs.  heavier  than  water,  viz.,  378  Ibs. 
Printed  instructions  for  use  accompany  each  Saccharometer. 

436  Brewer's  Saccharometer  Glass,  showing  pounds  per  barrel  (fig.  436)    056 

437  Ditto          ditto          with  Extra  Scale  showing  Specific  Gravity  and 

Ibs.  per  barrel 076 

438  Ditto        ditto        Glass  Testing  Jar  with  Tables  of  Temperature 

Corrections,  in  Mahogany  box,  with  Thermometer  as  fig.  425         .     0  15     6 

439  Saccharometers,  Glass  Standard,  comprising  two  instruments  in 

mahogany  case,  one  Saccharometer  ranging  from  0  to  25  Ibs.,  and 

the  other  25  Ibs.  to  50  Ibs.,  very  carefully  adjusted        .        .        .220 





FIG.  440. 

FIG.  441*. 


Saccharometer,  Double   Gilt  Metal,  with  silver  soldered  joints,  with  one 
weight,  metal  scale,  enamelled  tube,  compared  Thermometer,  with  expansion 
scale  and    rule,  in    mahogany   case,  with   lock    and  key,  Glass  assay  jar 
(figs.  440  and  441*),  and  book  of  directions  for  use         .        .        .500 
This  Saccharometer  can  be  strongly  recommended  both  for  strict  accuracy  and 
the  very  highest  class  of  workmanship. 

441    Saccharometer,  Metal,  Improved  with  double  Scales  extending  from  water  to 
25  Ibs.  per  barrel  on  one  side  of  the  upper  stem,  and  by  the  use  of  the 
weight,  the   opposite   scale   will  test  wort  from  25   Ibs.  to    52  Ibs.   per 
barrel  not  Gilt,  Glass  assay  jar         .         .         .         .         .         .         .330 

Ditto,        ditto,        Double  Gilt,  including  Thermometer,  Rule,    and   Book 
of  instructions,  in  box 400 


45,    CORNHILL,    E.G.,    AND    122,    EEGENT   STREET,    W.,    LONDON. 


FIG.  444. 

444  Negretti  and  Zambra' s  Patent  Saccharometers,  as  supplied  to  the  Excise 
Department  of  the  Inland  Revenue. 

The  changes  in  the  scale  divisions  of  Saccharometers,  required  by  the  New 
Beer  Act,  having  been  completed,  Messrs.  Negretti  and  Zanibra  are  now  prepared 
to  supply  their  Patent  Glass  Saccharometers,  and  also  a  new  form  of  Brass 
instrument,  made  in  accordance  with  the  models  supplied  by  them  to  the  Excise 
Department  of  Inland  Revenue.  Negretti  and  Zambra  having  been  favoured  with 
instructions  to  furnish  designs  for  special  instruments,  have  introduced  those 
mentioned  above,  each  kind  being  of  Standard  accuracy,  and  moderate  in  price. 

Fig.  444  consists  of  two  Patent  Standard  Glass  Saccharometers,  with 
strengthening  rods,  one  with  divided  scale  ranging  from  1,000  to  1,050  Specific 
Gravity;  the  other  from  1,050  to  1,100  Specific  Gravity;  also  a  brass  scale 
Thermometer.  The  three  instruments  are  fitted  in  a  strong,  well-made  Mahogany 
Box  as  supplied  to  the  Excise Price  £220 

A  set  of  three  Patent  Glass  Saccharometers,  the  scales  ranging  from  995  to 
1,150,  also  a  Brass  scale  Thermometer.  The  four  instruments  fitted  as  above  £2  15  0 

Glass  Saccharometers  being  much  more  accurate  than  those  made  of  metal, 
Negretti  and  Zambra  strongly  recommend  their  use,  especially  as  the  risk  of 
breakage  is  now  much  diminished  by  the  introduction  of  their  Patent  arrangement 
for  strengthening  the  weak  parts  of  the  instruments. 

FIG.  445. 

In  most  of  the  large  breweries  the  Standard  instruments  used  are  invariably 
Glass  ones,  as  greater  reliance  can  be  placed  upon  them,  more  especially  when 
indicating  the  fractional  parts  of  gravity. 

Fig.  445  is  a  Gilt  Metal  Saccharometer,  the  scale  on  one  side  of  its  stem  ranging 
from  995  to  1,025  Specific  Gravity  ;  and  on  the  opposite  side,  by  the  addition  of  a 



£    B.    d. 

Poise  (or  Weight)  is  a  scale  indicating  from  1,025  to  1,060.     This  also  has   a 
Thermometer  supplied  with  it,  and  is  fitted  in  a  Mahogany  Box,  being  arranged 

for  use  in  Distilleries  (fig.  445) Price  £2    5    0 

The  same  instrument  is  supplied  with  a  range  of  scale  suitable  for  Brewers' 

use,  viz. :  1,000  to  1,050,  and  1,050  to  1,100 Price  £2  10    0 

Messrs.  Negretti  and  Zambra  also  supply  a  simpler  form  of  Saccharometer,  the 
whole  range  of  scale  being  contained  in  one  instrument. 

Any  modification  of  the  above  arrangements  can  be  made  to  suit  the  require- 
ments and  convenience  of  purchasers. 
446    Combined    Glass    Hydrometer    and    Saccharometer, 
2  Scales  showing  Specific  Gravity  and  Ibs.  per  barrel, 
with  Thermometer,  in  mahogany  case  .... 
Saccharometer  Thermometer,  with  enamelled  tube  and 

expansion  scale,  mounted  on  Silvered  Brass  Scale 
Saccharometer  Can,  for  testing  Wort,  Copper,  tinned 


Ditto,  ditto  Tin  Japanned 

Glass  Saccharometer  testing  or  sample  jars  (fig  417) 
450*  Graduated  Glass  Blending  Jars,  for  wine,  spirits,  or 
beer  (figs.  450  and  441*)        ....        4s.  6d. 
451    Small  Glass  Hydrometer,  specific  gravity  scale,  with 
sample  glass  and  thermometer  in  case  (figs.  418  &  418*) 




£    s.    d. 


0  14    0 


0  10 
0  4 
0  3 

056        076 

0  15    0 

452  Small  Glass  Hydrometers  in  Pocket  cases  of  various  scales  and  range  made  to 


500  -^-j 



FIG.  456.    FIG.  512.        FIG.  453.          FIG.  450.      FIG.  453*.      FIG.  512.  FIG.  462. 

453  Small  Glass  Hydrometers,  two  in  the  set,  Specific  Gravity  Scale, 

from  water  to  sulphuric  aether,  or  from  water  to  sulphuric  acid, 

in  neat  case  with  Thermometer  and  Test  jar  (figs.  453  and  342*)        1  10    0 

454  Sets  of  eight  small  Glass  Hydrometers,  specific  gravity,  full  range 

from  tether  to  sulphuric  acid,  with  Thermometer  and  sample  jar  in 
case     .         .         .         .         .         .         . 

456  Twaddell's  Hydrometers,  Nos.  1,  2,  3  (fig.  456)        .       '.       *  each 

457  Ditto  ditto,  Nos.  4,  5,  and  6 do. 

458  Set    of    six    Twaddell's   Hydrometers,    in   mahogany   case   with 

Thermometer  graduated  on  the  stem,  and  test  glass        .        .        .220 


45,    COBNHILL,    B.C.,    AND    122,    REGENT    STREET,    W.,    LONDON.  183 

459  Twaddell's   Hydrometers,  so  named  after  their  inventor,  Mr.  Twaddell  of 

Glasgow,  are  very  largely  used  by  Dyers,  Bleachers,  and  Paper  manufacturers, 
the  six  instruments  having  an  extended  or  very  open  scale,  figured  from 
0,  Water,  to  170,  about  the  gravity  of  the  strongest  Sulphuric  Acid.  Each 
degree  or  division  of  Twaddell's  scale  being  equal  to  five  degrees  of  specific 

460  7  Comparative  Scale  showing  the  values  of  Twaddell's  Hydrometers,  Nos.  1  to  6 
in  Specific  Gravity. 

No.  Twaddell's  Scale.  Specific  Gravity. 

1  0    to    25  1-000  to      -125. 

2  25     „     50-  1-125     „       -250. 

3  50     „     75  1-250    „     1-375. 

4  75     „  100  1-375     „       -500. 

5  100     „  125  1-500    „       -675. 

6  135     „  170  1-675     „       -850. 
Twaddell's  Hydrometers  if  for  use  in  hot  climates  are  specially  tested  and 

adjusted  at  84°  Fahrenheit  at  an  extra  cost  of  6d.  on  each  instrument.  Each. 

461  Aquarium  Hydrometer,  for  showing  the  density  of  Salt  or  Sea  Water  £    s-    d- 

(fig.  424°) .        .        .036 

462  Board  of  Trade,  Marine  Hydrometers,  for  taking  the  specific  gravity 

of  Sea  Water  '0  to  '40  (fig.  462) 056 

463  Ditto        ditto,        2  Hydrometers  with  very  open  scale,  0  to  40° 

and  20  to  40° 0  10    0 

464  Sea  Water  ranges  in  Specific  Gravity  from-1-020  to  T036,  the  ordinary  gravity 
varying  between  T026  to  1'028.     Mediterranean  Sea  Water  about  T030,  and  that  of 
the  Caribbean  Sea,  1-040.     The  water  of  the  Dead  Sea  has  the  extraordinary  density 
of  1-200  to  1-250,  the  saltest  water  known. 

THE  SALTNESS  OF  SEA- WATER. — Professor  Chapman,  of  University  College, 
Toronto,  says  that  the  object  of  the  saltness  of  sea-water  is  to  regulate  evaporation. 
If  any  temporary  cause  raises  the  amount  of  saline  matter  in  the  sea  to  more  than 
its  normal  value,  evaporation  goes  on  more  and  more  slowly.  If  the  value  be 
depreciated  by  the  addition  of  fresh  water  in  undue  excess,  the  evaporation  power 
is  the  more  increased.  He  gives  the  results  of  various  experiments  in  reference  to 
evaporation  on  weighed  quantities  of  ordinary  rain-water  and  water  holding  in 
solution  2'6  per  cent  of  salt.  The  excess  of  loss  of  the  rain-water  compared  with  the 
salt  solution  was,  for  the  first  twenty-four  hours,  0'54  per  cent.,  at  the  close  of 
forty-eight  hours,  T46  per  cent ;  and  so  on  in  an  increasing  ratio. 
Analysis  of  sea-water  taken  from  the  English  Channel : — 

Chloride  of  Sodium 1891-6 

Chloride  of  Magnesium 228-4    ' 

Chloride  of  Potassium 47*8 

Iodide  and  Bromide  of  Magnesium      .        .        .         15-4 

Sulphate  of  Magnesia 145-4 

Sulphate  of  Lime 94-5 

Grains  per  gallon        .    2423-1 

These  quantities  vary  with  the  locality  as  well  as  the  percentage  of  -  Organic  Matter 
also  found  in  Sea  Water. 

The  ordinary  surface  Temperature  of  the  Sea  in  temperate  climates  is  45°  to 
51-5°  Fahr. 

"  In  most  parts  of  the  world  the  average  temperature  of  the  ocean's  superficial  water  is 
nearly  that  of  the  air  upon  its  surface.  In  the  tropics  the  temperature  of  the  sea  water 
ranges  from  70°  to  80°  Fahr.  or  more,  and  the  air  is  much  the  same.  In  some  limited  parts 
of  the  globe  the  surface  water  is  as  warm  as  86P,  for  instance,  near  the  Galapagos  Islands  ; 


and  in  some  very  confined  localities  even  more  than  90°,  as  for  example  in  parts  of  the  Eed 
Sea  and  Indian  Archipelago.  But  although  so  warm  on  the  surface  it  is  very  much  colder 
at  a  few  hundred  fathoms  below,  the  temperature  decreasing  to  35°,  and  even  less." 

£   s.    d. 

465  Universal  Hydrometer,  for  all  fluids  from  -700  to  1-900     .        .        .    0  12    0 

466  Confectioners'  Hydrometer  for  Ice  making  ...        3s.  6d.  and  056 

467  Ditto  ditto  for  Syrups  (see  also  No.  396)  .        .        .056 

468  Hydrometer  for  Brine.    A  saturated  solution  of  sea  salt  varies  between 

1-1962  and  1-205  at  60°  Fahrenheit 056 

469  Hydrometer  for  British  Wines  (Roberts'  scale,  0  to  26°)   .        .        .056 

470  Ditto,  for  Syrups  (Specific  Gravity) 056 

471  Ditto,  for  Soap  (Beaurne's) 056 

472  Ditto,  for  Soap  Lye  (Specific  Gravity) 056 

473  Olaeometer,  for  fixed  oils,  such  as  Sperm,  Linseed,  Rape,  &c.    .        .056 
From  a  competent  authority  we  quote  the  following  gravities : — 

474       Linseed  Oil     ,        .        .        .    0-9347 
Almond  Oil    .        .        .        .     0-9180 
Castor  Oil       .        .        .        .09611 
Palm  Oil         ....    0-968 
Oil  of  Turpentine    .        .        .    0-870 

Olive  Oil         ....  0-9176 

Rape  Seed  Oil         .        .        .  0*9136 

Colza  Oil         ....  0-9136 

Nut  Oil 0-9260 

Whale  Oil  ,  0  923 

475  Acidometer,  for  estimating  the  strength  of  Acids  (fig.  420)        .        .066 

476  Acetometer  (or  Acetimeter),  for  Vinegar    .        .       .       .       .       .066 

"  Specific  Gravity  if  determined  by  a  Sensitive  Hydrometer  is  a  good  test  of 

the  strength  of  genuine  Yinegar.     The  following  table  of  Messrs.  Taylor  is  nearly 
correct,  or  sufficiently  so,  for  commercial  transactions. 

"  Revenue  Proof  Yinegar,  called  by  the  English  manufacturer  "No.  24,  has  a 
Specific  Gravity  of 

1*0085,  and  contains  of  real  acid  in  100       ...      5 
1-0170  „  „  ......    10 

1-0257  „  „  „      ....    15 

1-0320  „  „  „      ....    20 

1-0470  „  „  „      ....    30 

1-0580  „  „  „      ....    40 

DR.  URE." 

It  should  be  observed  that  all  Malt  Yinegars  contain  mucilage,  gluten,  or 
saline  particles,  which  would,  to  a  certain  extent,  veil  the  indications  of  the 
Hydrometer ;  therefore,  if  precise  accuracy  be  required,  recourse  must  be  had  to 
Chemical  Tests  such  as  will  be  found  described  in  all  modern  Chemical  Books. 

477  Barktometer  Glass  for  Tanner's  use,  from  0  to  50      .        .        .        .076 

478  Ditto  ditto,  0  to  80,  divided  to  i  degrees 0  10    6 

479  Barktometer,  Gilt    Metal,  0    to   80,  divided   to   |   degrees  with 

Thermometer,  in  Mahogany  Box 330 

480  Citrometer,  for  Lime  or  Lemon  Juice,  as  used  by  the  Commissioners 

of  Customs,  specific  gravity  scale  from  0  to  100  in  two  instruments 
for  greater  accuracy,  complete  with  computing  rule,  and  a  delicate 

Thermometer  in  a  case 1  16    0 

Like  Yinegar,  Lime  or  Lemon  Juice  often  contains  a  very  large  percentage  of 
mucilage,  so  that  the  indications  of  the  Citrometer  should  only  be  regarded  as 
approximate  and  not  absolute.  We  also  find  that  by  the  Act  of  Parliament 
August  26th,  1867,  30  &  31  Yict.,  cap.  124,  Lime  or  Lemon  Juice  for  sbip's  use 
is  to  contain  "  fifteen  per  centum  of  proper  and  palatable  proof  spirits."  Chemical 
Tests  must  therefore  be  resorted  to  where  definite  results  are  desired. 

481  Negretti  and  Zambra's  Hydrometer  with  Thermometer  in  the  stem 

showing  density  and  temperature  in  one  instrument.    Fig.  481     .     1  10    0 

45,    CORNHILL,    E.C.,   AND    122,    REGENT    STREET,    TT.,    LONDON.  185 

FIG.  482,    FIG.  491. 

FIG.  486. 

*  " ^ 

FIG.  489.  FIG.  484. 


IT  is  a  matter  of  great  importance  in  rural  and  domestic  economy  that  we  have  a 
ready  means  of  ascertaining  the  Quality  of  Milk  yielded  by  different  cows.  The 
richness  of  milk^depending  upon  the  quantity  of  oil  or  butter,  and  curd  or  cheese 
which  it  contains,  it  becomes  necessary  that  we  be  able  to  determine  these  quantities 
with  facility  and  precision. 

To  attain  these  ends,  Messrs.  NEGRETTI  &  ZAMBRA  have  introduced  a  simple 
form  of  Lactometer,  by  which  the  richness  of  milk  may  be  determined  by  simply 
taking  its  temperature  and  specific  gravity. 

The  Lactometer  consists  of  a  glass  ball  and  stem  containing  a  graduated  scale 
ranging  from  0°  (water)  to  40Q  specific  gravity,  adjusted  to  a  temperature  of  60° 
Fahrenheit.  A  Glass  Jar  and  Thermometer  usually  accompany  the  instrument. 

482  Lactometer  of  a  simple  form  for  household  use.     The  top  of  the  scale  is 
marked  O  and  W,  indicating  water,  and  at  the  lower  end  P  signifying  pure  milk. 
Intermediate  between  these  two  points  are  marks  indicating  ^  milk  and  f  water, 
£  milk  and  ^  water,  f  milk  and  i  water.     These  marks  must  not  be  taken  as  abso- 
lute, for  pure  milk  will  vary  in  quality  or  density  according  to  the  particular  kind 
of  food  upon  which  the  cows  have  been  feeding  (fig.  482)          .    '     .        .£036 

483  Lactometer  similar  to  above  but  with  an  additional  scale  on  the  back 
showing  specific  gravity £050 

484  Lactometer,  Negretti  and  Zambra's  Lactometer  of  superior  accuracy,  with 
absolute  Specific  Gravity  scale,  with  printed  instructions  for  use  (fig.  484)  £0     5     0 



485  Lactometer    Tubes,    or    Creamo-meters,    graduated  to    show   the 

percentage  of  cream  ;  a  set  of  six  in  mahogany  frame    .         .         .     0  16     6 

486  Ditto,  a  set  of  three  tubes  in  frame  (fig.  486)     .         .         .     0  10     6 

489  Cream  Test  Jars,  graduated  to  show  percentage  (fig.  489)  .056 
Ditto            ditto,     smaller .         .         .         .036 

490  Thermometer,  add  or  subtract,  for  use  with  above.     (See  also  Dairy 

Thermometers) 076 

491  Lactometer  Glass,  with  Thermometer  and  Test  Jar,  in  Mahogany 

Box  (as  fig.  425) 150 

492  Thermometers  for  Dairy  Use  entirely  mounted  in  glass  (fig.  492) 

3s.  6d.  and    056 

493  Lactometer,  Gilt  Metal,  Specific  Gravity  Scale  .        .        .    12s.  6d.    1    5    0 

494  Ditto,       ditto       Gilt  Metal  with  Thermometer  and  Test  Jar,  in 

Mahogany  Box  (as  fig.  425) ,         .220 

495  Centesimal  Galactometer,  Glass  (Dr.  HassaU's)         .       .       .       .    0  10    6 
Lactometers  being  adjusted  to  a  temperature  of  60°  Fahr.,  all  trials  must  be 

made  at  that  temperature.  Should,  however,  that  be  inconvenient,  then  for  every 
five  degrees  of  diiference  in  temperature,  make  a  difference  of  one  degree  on  the 
Lactometer  scale,  adding  the  degrees  of  temperature  if  above  60°,  and  subtracting 
them  if  below  GO0.  For  greater  convenience,  Thermometers  are  made  by  NEGRETTI 
and  ZAMBRA  to  show  at  a  glance  the  amount  to  add  or  subtract  for  difference  of 



For  Cows'  Milk  .  .  .  .  26  to  38 
„  Cows'  do.  (grass-fed)  before 

being  Creamed  .  .  . 32 

„  Cows'  milk  (grass-fed)  the 

cream  being  taken  off  . 38 

„  Woman's  ditto  .  .  .  28'—  38 

„  Ass's  ditto  ,  30  —  34 

For  Goat's  do.  (house-fed)     .         .30  —  34 
„    Milk     of     Ewes     (grass-fed) 

before  being  creamed .        . 36 

,,    Ditto  ditto,  the  cream  being 

removed       .        .        .         . 46 

„    Mare's  milk     .        .        .        . 36 


497  Sheffer's  Hydrometers,  one  from  '700  to  1000,  the  other  from  1000  to  T900 

with  solution  tube,  per  pair  (figs.  453  and  453*)       .        .        .        .    0  15     0 

498  Cartier's  Hydrometer,  chiefly  used  in  France  for  testing  fluids  lighter  than 

water.  It  is  a  modification  of  Baume's  spirit  hydrometer,  the  same  point 
being  taken  as  the  zero  of  the  scales.  The  space  which  in  Baume's  scale  is 
divided  into  32°,  is  in  Cartier's  divided  into  30°  .  .  .  .060 

499  Gay  Lussac's  Alcohometer  or  Hydrometer,  for  testingjthe  strength  of  spirits — 

mostly  used  in  France.  The  scale  is  divided  into  100  parts,  the  lowest 
division,  marked  0  at  the  bottom  of  the  scale,  denotes  the  specific  gravity  of 
pure  water  at  a  temperature  of  15°  Cent,  or  59  Fahr.  The  highest  division 
at  the  top  of  the  scale  indicates  the  specific  gravity  of  absolute  alcohol  of 
sp.  gr.  '796  at  the  same  temperature.  The  intermediate  degrees  indicate 
the  number  of  volumes  of  such  alcohol  in  100  volumes  of  the  spirit 
tried 060 

500  Baumes'  Saccharometer  floats  at  30°  in  a  solution  the  Specific  Gravity  of  which  is 
1'26 — this  is  the  density  of  Simple  Syrup  when  boiling  ;  hence  if  the  Saccharometer  floats 
at  30°  in  a  solution  of  Sugar,  when  boiling  it  is  inferred  that  such  solution  will  be  exactly 
saturated  when  cold.    The  scale  is  sometimes  graduated  to  indicate   the  proportion  of 
Sugar  in  the  solution  under  examination. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  187 

Q       O 

FIG.  492. 

PAGE  168. 

FIG.  514. 

FIG.  517. 

FIG.  513. 

501  Fahrenheit's  Hydrometer  has  two  glass  bulbs  blown  on  a  tube  similar  to  the 
ordinary  hydrometer,  the  upper  bulb  being  the  larger.     The  top  of  the  stem  is 
terminated  by  a  small  cup  or  dish.     The  lower  bulb  is  weighted  with  mercury 
sufficient  to  cause  the  partial  immersion  of  the  instrument  when  placed  in  water 
without  any  weights  being  placed  in  this  cup.     In  the  middle  of   the  stem  is 
a  mark,  to  which  point  the  hydrometer  is  adjusted  in  water  by  placing  weights  in 
the  cup.     Its  use  is  similar  to  that  of  Nicholson's  Gravimeter.  £0  10     6 

502  Densimeter,  a  modification  of  Fahrenheit's  instrument, 

chiefly  used  in  France 0  12     6 

503  Richter's  and  TraUe's  Hydrometer,  with  Thermometer      .        .       .    0  15    6 

504  Normal  Alcoholometer,  Tralle's,  used  in  Prussia  and  the  United 

States,  has  a  scale  figured  from  0°  to  100°,  each  degree  repre- 
senting one  per  cent,  by  volume  of  Alcohol,  Specific  Gravity 
07939  in  any  mixture  of  Alcohol  and  Water  at  60  degrees  temper- 
ature Fahrenheit 0  14  0 

505  Wooley's     Hydrometer.      This    instrument    has    2    scales,    viz., 

Government  Proof  and  Specific  Gravity 066 

506  A  set  of  five  Standard*  Glass  Hydrometers.    Government  Proof 

Scale,  forty  under  Proof  to  sixty  over  Proof,  with  a  very  accurate 
Thermometer  in  a  Mahogany  Box,  with  Book  of  Tables  as  used 
with  the  metal  Hydrometer 400 

507  Hermbstadt's  Hydrometer  and  Saccharometer,  having  two  Scales, 

one   showing  Specific  Gravity,  I'OOO  to  T321  and  percentage  of 

Sugar  0  to  67 066 


FIG.  515.  .  FIG.  515*. 

Each  Each 

£     s.    d  £     s.    d. 

508  Volumeter  (Gay  Lussac's),  for  liquids  lighter  or  heavier 

than  water 066 

509  Densimetre  (Gay  Lussac's),  for  liquids  lighter  or  heavier 

than  water,  in  two  spindles  simple  form        ...  086 

510  Ditto  •  (Rousseau),      for  ditto  ditto        ditto    .  086 

511  Photographic  Hydrometer,  or  Argentometer,  showing 

grains  per  ounce  of  nitrate  of  silver  in  solution   .  036 

512  Hydrometer     Test     Glasses,     or     Jars,     on     foot 

(figs.  512  and  515*) 2s.    0    3    6        056 

513  Salinometer  Glass,  for  ascertaining  the  density  of  salt 

water  in  steam-boilers,  to  prevent  incrustation  (fig  471.)  056 

514  Ditto  ditto,  Gilt  Metal,  in  tin  case  (fig.  466)  0  18    0 

515  Ditto  Ditto,  Gilt  Metal  or  German  Silver  in  Box,  fig.  467  1    1    0 

516  Ditto  with  Thermometer  in  Mahogany  box     ...  1  12    0 

517  Salinometer  Thermometer  (fig.  469)        .  066 

518  Ditto,  Testing  Pot,   Stout    Copper,  with   division  for 

Thermometer. 086 

The  Salinometer  used  for  testing  the  density  of  water  in  Marine  Steam  Boilers 
has  a  scale  with  five  principal  divisions  marked  upon  it,  the  first  division  on  the 
top  of  the  stem  is  marked  0,  representing  pure  water,  the  others  marked  3'2  |2  3$ 
and  345  signify  that  when  the  Salinometer  floats  at  any  of  these  divisions,  that  the 
water  contains  1,  2,  3,  or  4  parts  of  saline  or  solid  matter  in  32  of  water. 

Between  525  and  335  is  engraved  the  word  Blow,  indicating  that  when  the  Boiler 
Water  has  reached  that  density,  a  portion  of  it  should  be  blown  out  of  the  boiler 
and  replaced  with  fresh  water.  The  temperature  at  which  the  water  is  to  be  tested 
is  200°  Fahr. 

At  the  325  the  word  "  Limit "  is  marked,  when,  at  that  indication,  it  becomes 
dangerous  to  work  it  beyond  that  strength  or  density. 

Thus,  this  Instrument  purports  to  indicate  the  precise  time  at  which  Marine 
Steam  Boilers  should  be  blown  off,  not  only  to  prevent  waste  by  blowing  off  too 
frequently,  but  to  avoid  the  possibility  of  the  Boiler  being  injured  by  the  deposition 
or  incrustation  of  the  salt,  which  is  a  bad  conductor  of  heat,  and  frequently  the 
cause  of  the  Boiler  being  burst.  The  engineer,  by  merely  looking  ab  the  scale  of 
the  Salinometer  as  it  floats  in  the  water,  can  at  once  ascertain  the  saline  density 
of  the  water  with  the  greatest  accuracy. 

45,    COENH1LL,    E.G.,    AND    122,    BEGENT    STREET,    W.,    LONDON.  189 


5 1 9  Fill  the  Assay  Jar  from  the  Boiler,  suspend  the  Thermometer  in  the  side 
partition  of  it,  and  immerse  the  Ball  in  the  water ;  then  at  whatever  division  on  the 
stem  it  rests  level  with  the  snrface,  will  be  the  degrees  of  saline  matter  contained 
in  the  water  at  the  temperature  of  200° ;  but  if  the  heat  of  the  water  varies  below 
that  degree,  the  following  scale  of  temperature  will  be  the  blowing-off  point : — 

TEMPERATUKE.  200°  -^1 

180°  |f  }  at  surface  for  Blowing-ofC  point. 
160°  sf  I 

Under  the  circumstances  at  which  fresh  water  boils  at  212°,  sea  water  boils 
at  213'2°.  The  boiling  temperature  is  raised  by  the  chemical  solution  of  any 
substance  in  the  water,  increasing  with  amount  of  matter  dissolved.  For  this 
reason,  marine  engineers  use  a  Thermometer  to  determine  the  amount  of  salts  held 
in  solution  by  the  water  in  the  boilers  of  sea- going  steamers.  Common  sea  water 
contains  about  -|s  of  its  volume  of  salt  and  other  earthy  matters.  As  evaporation 
proceeds,  the  solution  becomes  proportionally  stronger,  and  more  heat  is  required 
to  produce  steam.  The  following  table  by  Messrs.  Main  and  Brown  shows  the 
relation  between  the  boiling  point  under  the  mean  pressure  of  the  atmosphere,  or 
30  inches  of  mercury,  and  the  proportion  of  matter  dissolved  in  the  water. 

When  the  salts  in  solution  amount  to  ||  the  water  is  saturated.  It  has  also 
been  ascertained  that,  when  a  solution  of  -§\  is  attained,  incrustation  of  the  sub- 
stances commences  on  the  boiler.  Hence  it  is  a  rule  with  engineers  to  expel  some  of 
tlie  saturated  water,  when  the  thermometer  indicates  a  temperature  of  216°  F,  and 
replace  it  with  fresh  water,  in  order  to  prevent  incrustation  and  injury  to  the  boiler. 

520    The  Boiling  point  of  Saturated  Solution  of  Salt  varies  from  218  degrees  to 
226  Fahr. 

Proportion  of  Salt  in  400  parts  of  water  0       .        .        Boiling  point  212° 

-53      •        •  „  213-2 





if      .         .  „  226-0 

For  further  information  on  this  subject,  see  Temperature  Thermometer  in 
conjunction  with  pressure  gauges,  page  151. 

521  Salinometer,  or  Salt  Water  Guage,  (How's  Patent),  constructed  of  strong  Gun 

Metal  and  Brass,  for  attaching  to  the  Boilers  of  Marine  Steam  Ships,  to 
ascertain  at  any  moment  the  specific  gravity  of  the  water  contained  in  the 
Boiler.  Complete,  with  Metal  Salinometer,  Thermometer,  and  Lamp ;  best 
finished  Gun  Metal  Tap  Unions  and  Yalves.  £880 

522  Salinometer,  Saunders £880 

523  Ditto,  Gambles  .  .£880 


624  Spirit  Gravity  Beads  are  small  light  hollow  spheres  made  of  white  or  coloured  glass 
about  half-an-inch  in  diameter,  with  a  stem  or  tail  of  about  a  quarter  of  an  inch  in  length. 
The  use  of  this  stem  is  for  adjusting  each  bead  to  a  certain  degree  of  Specific  Gravity,  or 
to  a  given  degree  of  Sike's  Hydrometer  Scale.  The  degrees  are  engraved  upon  each  Bead, 
thus  forming  them  into  rough  Hydrometers  for  ascertaining  the  Gravity  of  various  Fluids  of 
Spirits.  When  the  Bead  floats  about  half-way  in  any  sample  of  liquid  to  be  tested,  the 
density  or  specific  gravity  of  such  liquid  is  indicated  by  the  figures  or  numbers  engraved 
upon  the  bubble. 

525  Salt  Water  Beads,  or  bubbles,  for  Aquaria        .         .         .     in  pairs  £020 

The  average  Specific  Gravity  of  Sea  Water  is  T026  to  1/028. 

Gravity  Beads  for  Aquaria  are  made  of  different  coloured  glass,  one  adjusted  to  float 
upon  the  surface  of  the  water,  and  the  other  to  remain  at  the  bottom  of  the  tank  when  the 
water  is  of  suitable  density  for  the  healthy  growth  of  fish  or  plants. 

£     s.    d. 

526  Specific  Gravity  Beads,  (or  Spirit  Bubbles,  Glasgow 

Beads),     for     showing     the     strength     of     spirits, 

set  of  twelve,  in  japanned  tin  box         ....  066 

527  Ditto,  ditto        .        .        .        .        set  of  eighteen  0  10    6 

528  Specific  Gravity  Beads,  for  heavy  and!  light  fluids,  such 

as  aether,  alcohol,  ammonia,  oil,  naphtha,  acids,  each  .  010 

529  Specific  Gravity  Bottles,  1,000  grains'  capacity,  in  tin  case 

with  counterpoise  weight.  (See  also  Chemical  Section.)  0  10    6 

530  Ditto  ditto  500  grains 086 

531  Ditto  ditto  250  grains 066 

532  Nicholson's  Gravimeter,  for  ascertaining  the    specific 

gravity     of     metals     or     other     solid     substances, 

Japanned  tin  (fig.  532)  with  Metal  Case        ...  0  10    0 

533  Nicholson's  Gravimeter,  larger  size,  accurately  made  in 

BRASS,  fitted  in  case,  with  weights  ranging  from  l-10th 

to  1,000  grains  (fig.  533)       ....  330 

Nicholson's  Hydrometer  or  Gravimeter  is  a  modification 
of  Fahrenheit's  instrument,  and  is  made  either  of  very  light  tin 
japanned,  or  gilt  brass ;  its  form  will  be  seen  in  fig.  532.  A 
mark  is  made  on  the  stem  supporting  the  cup  to  which  the 
instrument  is  adjusted  by  weight  to  float  in  water.  The  weight 
of  the  loaded  instrument  when  sunk  to  this  point  is  the  weight 
of  the  volume  of  liquid  displaced  by  it.  It  gives,  therefore,  the 
relative  weights  of  equal  volumes  of  the  liquids  into  which  it  is 
placed.  The  Gravimeter  is  usually  made  to  displace  3,000  or 
4,000  grains  of  water,  and  is  sensible  to  the  tenth  of  a  grain  in 
this  quantity.  With  this  instrument  the  'specific  gravity  of 
„...,.,  solids  may  also  be  ascertained.  By  placing  the  solid  to  be  tested 

IG*  ifilllpl  in  the  cup  on  the  top  of  the  stem  and  adjusting  the  additional 

weights  required  to  sink  the  Hydrometer,  the  weight  of  such 
solid  body  in  air  is  found.  Then  by  placing  the  solid  in  the 
lower  cup  immersed  in  the  water,  and  again  adjusting  the 
weights  as  before,  the  weight  of  the  solid  in  water  is  ascertained; 

F       533      ^     and  f rom  tliese  two  resuits  tne  specific  gravity  is  calculated. 

45,    CORNHILL,    B.C.,   AND    122,    REGENT    STBEET,    W.,    LONDON. 



534  To  find  the  specific  gravity  of  a  mineral  or  other  solid,  place  weights  in  the  upper  cup 
sufficient  to  sink  the  Hydrometer  to  the  mark  on  the  stem  when  the  Hydrometer  is  floated  in 
distilled  water,  and  call  this  weight  A.  Now  take  a  piece  of  mineral  of  less  weight  than  A  ; 
place  this  in  the  upper  cup,  and  add  weights  until  the  Hydrometer  sinks  to  the  same  mark 
as  before.  Call  the  weights  added  B.  Remove  the  solid  from  the  upper  cup  to  the  lower, 
allowing  the  weights  to  remain  in  the  upper  cup.  Add  weights  until  the  Hydrometer  sinks 
to  the  mark  on  the  stem,  and  call  the  additional  weights  C.  Subtract  B  from  A,  and  divide 
the  remainder  by  C,  and  the  quotient  is  the  specific  gravity. 

Thus,  suppose  the  specific  gravity  of  a  specimen  of  fluor-spar  is  required.  First,  on 
trial,  we  find  that  460  grains  placed  in  the  upper  cup  will  sink  the  Hydrometer  to  the  mark 
on  the  stem  when  floated  in  distilled  water — consequently,  A  is  equal  to  460  grains ;  and 
that  when  the  fluor-spar  is  placed  in  the  upper  cup,  92  grains  must  be  added  to  sink  the 
Hydrometer  to  the  same  level  as  before — then  B  is  equal  to  92  grains.  Now,  on  removing 
the  fluor-spar  to  the  lower  cup,  115  grains  must  be  added  to  the  92  grains  still  remaining  in 
the  upper  cup  to  sink  the  Hydrometer  to  the  same  mark  as  before  ;  therefore  C  is  equal  to 
115  grains.  Then 



Censequently,  3-2  is  the  specific  gravity  required. 

In  our  Chemical  Section  will  be  found  and  described  Balances  arranged  to 
exhibit  the  same  facts  with  extreme  precision. 







FIG.  539. 

FIG.  538. 

Urinometer,  for  ascertaining  the  Specific  Gravity  of  Urine,  of  two 

forms,  figs.  444  and  444* 

Ditto,  ditto,  in  round  leather  pull-off  case,  with  graduated  test  glass 

Ditto  ditto,  in  case 

Ditto  ditto,    with  test  glass  and  thermometer, 

Ditto,  ditto,  in  hinged  Leather  case,  fitted  up  with  thermometer, 

spirit   lamp,   acid  bottle,   test  tubes,  dropping  tube,  graduated 

jar,  test  papers,  &c.  (fig.  538) 

Urinometer,  larger  case,  and  more  complete,  with  extra  stoppered 
and  cut  test  bottles  and  evaporating  dishes,  tube  holder,  &c. 

(fig.  539) 2 

Metal  Urinometer,  Gilt  or  Plated,  in  pull-off  case  .    0 

Urinometer  Test  Papers,  various per  book    0 

s.  a. 




1  10    0 



FIG.  445. 

FIG.  444.    FIG.  444*.         FIG.  449. 

544  The  Urinometer  originally  suggested  by  Dr.  Prout  for  ascertaining  the  density 
of  urine  has  a  scale  divided  into  60  degrees,  the  zero  being  the  point  at  which  the 
instrument  floats  in  distilled  water  at  a  temperature  of  60°  Fahrenheit. 

The  numbers  on  the  scale  added  to  1,000  (the  assumed  specific  gravity  of  water) 
give  the  specific  gravities  at  the  respective  points.  If  the  number  cut  by  the  sur- 
face of  the  fluid  under  test  be  30,  it  indicates  a  specific  gravity  of  T030.  On  the 
reverse  side  of  this  scale  will  be  found  the  letter  W  at  the  top,  on  the  same  line  as 
the  0  indicating  water.  Lower  down  the  scale  is  a  space  marked  H,  signifying 
healthy  standard,  which  ranges  from  10°  to  20°  of  the  scale.  The  space  from  30°  to 
60°  is  marked  diabetes,  the  urine  of  diabetic  patients  generally  ranging  between  these 
points.  See  figs.  444  and  444*. 

545  Dr.  Lionel  Beale's  Clinical  Cabinet  arranged  as  a  companion  to  Dr.  Beale's 
work,  The  Microscope  in  its  Application  to  Urinary  Analysis.  &c.,  &c. 

CONTENTS  : — Urinometer  in  sheath,  2  oz.  graduated  measure,  glass  pipette,  stir- 
ring rod,  test  tubes,  watch  glasses,  glass  slips,  and  thin  glass  covers,  glass  spirit  lamp, 
test  tubes,  holder,  test  papers,  8  improved  capped  dropping  bottles  (fig.  489)  in  ebonite 
rack,  for  containing  the  following  re-agents :  acetic  acid,  nitric  acid,  ammonia,  potash, 
nitrate  of  barytes,  nitrate  of  silver,  oxalate  of  ammonia,  &c.  (fig.  445)  .£330 

546  Urea  Tubes  divided  to  lOOths  of  a  cubic  inch 

547  Improved  Dropping  Bottles,  fig.  447 
547*  Dropping  Tubes  or  Pippettes  Glass     . 



6d.,  8d.    0    1    0 

45,    CORNHILL,    E.G.,   AND    122,    REGENT    STREET,    W.,    LONDON.  193 

FIG.  551. 

FIG.  550. 

FIG.  552. 

FIG.  557. 

548  Alcoholometer,  Field's  Patent,  for  ascertaining  the  original  gravity  of  every 

description  of  ale,  stout,  or  porter,  at  any  period  after  fermentation.  This 
apparatus  is  useful  for  testing  comparatively  various  samples  of  beer, 
returned  beer,  and  also  beer  for  export.  Price,  complete  in  mahogany  box, 
with  directions  for  use,  and  correction  tables  of  variation  .  £600 

549  Wine  or  Spirit  Analyser,  Long's  Patent,  for  ascertaining  the  quantity  of 

alcohol  in  wines,   cordials,   &c.,  in  accordance  with  Treasury  Order  of 

July  12, 1853,  fixing  the  maximum  of  spirit  in  wine  at  33  per  cent.  £4  10    0 

Graduated  Glass  Measure  Standard  for  use  with  above       .        .        £036 

550  Distilling  Apparatus ;  or,  Phillips'  Revenue  Standard  Still,  for  ascertaining 

the  original  gravity  of  Beer  after  fermentation,  &c.;  of  strong  brazed  copper, 
with  two  Trial  Jars  and  Thermometer,  Pipette  or  Dropping  Tube,  &c. 
(fig.  550) £550 

This  apparatus  is  also  used  for  the  Alcoholic  Wine  Test  by  the  Board  of 
Customs  for  estimating  the  amount  of  Alcohol  contained  in  Wines  and  Liqueurs. 

Gas  Burner,  improved  for  above  (fig.  551) £0  12    6 

Gilt  Metal  Hydrometer,  pocket  size  for  use  with  above  apparatus, 

in  neat  case  (fig.  552) £0  16    0 

Gilt  Metal  Saccharometer,  pocket  size  for  ditto  in  case       .       .       £0  16    0 
Glass  Flasks  for  Still,  with  metal  screw  fittings  .        .        .        .        £046 




Sikes'  Hydrometers,  for  use  in  connection  with  the  above,  see  pages  178,  179. 




556  Attach  the  water  supply,  which  may  be  a  Cistern  or  Cask  placed  four  feet  above  the 
Condenser,  the  connection  being  by  Flexible  Tube  from  the  Tap  of  the  Cistern  ;  the  outflow 
of  water  is  to  be  conducted  into  a  pail,  the  quantity  used  being  regulated  by  the  Cock  in 
the  Cistern  ;  and  the  water  having  been  found  to  flow  through  the  Condenser  in  a  con- 
tinuous stream,  the  Gas  Lamp  should  be  connected  also  by  means  of  Flexible  Tube,  with  a 
Gas  Pipe,  and  lighted  on  the  top  of  the  Gauze.  Where  Gas  is  not  obtainable,  a  large  Spirit 
Lamp  can  be  used. 

To  Test  a  Sample  of  Wine.— Fill  the  Measure  Flask  with  Wine  to  the  highest  mark, 
adjusting  the  exact  quantity  by  using  the  Pipette  ;  pour  the  measured  Wine  into  the  Still 
Flask,  rinsing  out  the  Measure  with  a  few  drops  of  water  which  must  be  added  to  the  Wine  ; 
the  measure  being  quite  clean,  is  placed  upon  the  bracket,  and  adjusted  to  receive  the 
Distilled  Wine  Spirit;  the  Still  Flask  is  then  to  be  screwed  tightly  to  the  condenser, 
interposing  an  Indiarubber  Washer  between  the  Flask  and  the  metal  shoulder  of  the  Still 
Pipe  ;  put  the  Lamp  under  the  Still  Flask,  at  first  moderately  burning,  afterwards  increase 
the  flame  ;  in  a  few  minutes  the  Wine  will  boil,  and  the  vaporised  Spirit  will  begin  to  con- 
dense, falling  into  the  Measure.  Repeated  experiments  have  proved  that  with  weak  Wine, 
such  as  contain  under  26  per  cent,  of  Proof  Spirit,  it  is  only  necessary  to  distil  over  one- 
half  the  bulk  ;  but  stronger  Wines,  containing  much  extractive  matter,  require  the 
operation  to  be  continued  until  two-thirds  are  distilled  ;  the  Standard  Measure  is  therefore 
graduated  at  two-thirds  as  well  as  one-half.  When  the  required  point  on  the  Measure  is 
obtained,  the  original  measure  of  the  Wine  (up  to  the  highest  mark)  is  to  be  made  up  with 
Water,  then  poured  into  the  Trial  Glass  and  stirred  well,  so  that  the  Spirit  and  Water  may 
be  perfectly  mixed :  with  the  Thermometer  the  temperature  should  be  observed,  the 
strength  being  taken  by  Sikes'  Hydrometer  according  to  the  usual  tables. 

To  insure  extreme  accuracy,  it  is  necessary  that  the  temperatures  of  the  Wine  before 
distillation,  and  the  Spirit  and  Water  before  taking  the  strength  by  the  Hydrometer,  should 
be  the  same,  that  the  two  bulks  may  be  identical. 

Accurate  Balances  and  Weights,  Specific  Gravity  Bottles,  Test  Jars,  Graduated 
Measuring  Glasses,  &c.,  &c.,  for  use  with  the  Distilling  Apparatus.  See  sections 
"  Thermometers,"  "  Hydrometers,"  and  "  Chemical  Apparatus." 

557  Negretti  and  Zambia's  Patent  Strengthened  Glass  Hydrometer,  fig.  557 
Of  all  glass  instruments  required  by  the  exigencies  of  Science,  the  Glass  Hydro- 
meter is  the  most  delicate  and  fragile.  Very  many  of  these  instruments  are  broken 
in  carriage,  and  very  recently  the  Government  of  India  requiring  a  large  number 
of  Hydrometers  for  fiscal  purposes,  applied  to  Messrs.  Negretti  and  Zambra  for 
assistance  in  procuring  an  Hydrometer  which  could  be  safely  sent  to  the  interior 
of  India.  Messrs.  Negretti  and  Zamba  submitted  some  instruments,  which  so  far 
fulfilled  the  conditions  required,  that  20,000  of  Messrs.  Negretti  and  Zambra's 
Patent  Hydrometers  were  ordered  and  supplied.  The  novelty  consists  in  insert- 
ing an  inner  tube  down  the  stem,  and  reaching  to  the  bottom,  and  there  being 
fastened  securely  to  the  neck  of  the  lower  bulb ;  it  will  be  seen  that  by  these  means 
the  weight  of  the  instrument  is  supported  from  the  bottom,  and  not  at  the  juncture 
of  the  stem  with  the  large  bulb,  where  usually  the  breakage  of  the  old  form  of 
Glass  Hydrometers  'took  place. 

Any  form  of  Hydrometer  described  in  the  preceding  pages  can  be  constructed 
with  Negretti  and  Zambra's  improvement  to  order  at  a  slightly  increased  expense. 

45,    COENHILL,    E.G.,    AND    122,   REGENT    STEEET,    W.,    LONDON.  195 

558  Comparative  Scales  (Baker's)  compiled  from  tables  of  eminent  authorities,  for 
the  use  of  Chemists,  Distillers,  Brewers,  Dyers,  Bleachers,  Paper  makers,  British 
Wine  makers,  Confectioners,  &c.,  &c. 

It  Comprises  Specific  Gravity  Scale,  TwaddeH'Sj'Baume's,  Cartier's,  Gray  Lussac's, 
Saccharometer  scale  of  Ibs.  weight  per  barrel,  Extract  per  barrel,  and  the  Govern- 
ment Proof  Spirit  scale.  Several  percentage  scales  for  Spirits,  Acids,  Chlorine, 
Ammonia,  Solutions  of  Potash,  Soda,  and  four  comparative  Thermometer  Scales;  viz., 
De  Lisle,  Centigrade  or  Celsius,  Fahrenheit,  and  Reaumur, — in  all  34  scales, 
containing  a  vast  amount  of  most  valuable  and  useful  information.  Price  2s.  each. 

Recent  Acts  of  Parliament  in  connection  with  the  adulterations  of  food,  drugs, 
&c.,  &c.,  will  often  necessitate  strict  investigation;  in  such  matters,  therefore, 
Messrs.  Negretti  and  Zambra  cannot  too  strongly  impress  upon  the  minds  of  their 
customers  the  great  importance  of  accuracy  in  all  apparatus  used  for  analysing  or 
testing  the  purity  or  strength  of  the  articles  under  examination. 

For  such  purposes,  N.  &  Z.,  from  their  great  experience  in  this  special  branch 
of  their  trade,  can  confidently  recommend  their  instruments. 

The  various  Areometers,  &c.,  &c.,  used  on  the  Continent  to  ascertain  the 
density  of  Liquids,  made  to  order. 

GAUGING  INSTRUMENTS,  RULES,   Ac.    See  Scales  and  Rules. 

Specific  Gravity  of  fluid  Mercury.  The  density  of  this  Metal  at  39-2°  F.,  is  13-588, 
according  to  Kupffer.  Hence  its  Specific  Gravity  near  the  point  of  congelation  will  be 

The  Specific  Gravity  of  solid  (frozen)  Mercury  is  stated  by  Kupffer  and  Cavallo  to  be 
about  14-0. 

According  to  Dufour,  the  Specific  Gravity  of  Ice  is  0-9178  ;  Bunsen  states  it  at  O91674. 

"  Sea  Water  freezes  at— 2'5°  to — 0°  C. ;  the  ice  which  forms  is  quite  pure,  and  a 
saturated  solution  remains.  If  water  contains  Alcohol,  precisely  analogous  phenomena  are 
observed  ;  the  ice  formed  is  pure,  and  all  the  Alcohol  is  contained  in  the  residue." — GANOT. 

"  M.  Despretz  by  the  cold  produced  with  a  mixture  of  liquid  Protoxide  of  Nitrogen, 
Solid  Carbonic  Acid,  and  jEther  has  reduced  Alcohol  to  such  a  consistence,  that  the  vessel 
containing  it  could  be  inverted  without  losing  the  liquid." 

Lowest  artificial  cold  produced  by  Chemical  Combination,  187°  below  Zero  F. — 
A.  S.  TAYLOE. 

Ditto         ditto  140°  C. — GANOT. 

Mercury  freezes,  37'9  Fah.— Kew.     Carbonic  Acid  Gas  Solid  at  148°  below  0°,  F. 

We  are  informed  that  lower  temperatures  have  been  recently  produced  ly  Chemical 




FIG.  562. 

FIG.  563. 

29  — 








*/  — 


19  — 

18  — 

17  — 

16  — 



IS  — 

)2  — 

JO  — 






— — 


-2  o 

FIG.  559. 

FIG.  564. 

£     s. 

2    2 
2  10 


559  Vacuum  Gauge,  in  Mahogany  or  Oak  frame,  form  as  fig.  459   . 

560  Ditto  ditto  in  Plain  Brass  frame    . 

561  Marine  Vacuum  Gauge,  in  Oak  frame,  iron  cistern,  stout  glass  tube, 

gun  metal  unions,  and  OPAL  GLASS  SCALES,  divided  to  1- 100th 

of  an  inch  . 440 

562  Vacuum  Gauge,     The  tube  and  scale  are  enclosed  in  stout  Glass 

cylinder  and  Brass  frame,  with  stop-cock  and  union  (fig.  562)        .     1  10     0 

563  Sugar  Pan  Vacuum  Gauge,  as  above,  in  Brass  case,  with  Hinged 

Door,  ground  plug,  fitting  with  Stop-Cock,  &c.  (fig.  563)         .         .     2  10     0 

564  Vacuum  Gauge,  to  show  30  inches,  in  handsome  Mahogany  case, 

with  plate  glass  front,  adjusting  glass  cistern,  Gun  Metal  Tap,  &c., 

suited  for  First-class  Engine  Rooms  (fig.  564)        .        .        .        .550 

For  Circular  Vacuum  Gauges,  see  Bourdon's  Gauges,  pages  206  to  209. 

45,    COBNHILL,    E.G.,    AND    122,    REGENT   STEMET,   W.,   LONDON. 



565  On  an  improved  principle,  with  Ebony  handle  spanners,  complete  mth  glass 

tube  and  vulcanised  rubber  rings  : — fig.  565. 

f -in.  30s,  £-in.  35s.  |-in.  40s.  f-in.  42s. 


566  Gauge  Tube,  for  Steam  Boilers,  &c.,  of  stout  annealed  glass,  manufactured 

expressly  for  this  purpose.    Various  lengths  and  diameters  cut  to  order, 
average  Id.  per  inch 

GAUGE   TUBES  of  the  best  quality  :— 

















12  „    | 




13  „    * 




14  „    f 




15  „    f 




16  ,,    1 




12   „    f 






8.  d. 

.  8  0 

13  by  f 

.  9  0 

14  „  I 

.  9  6 

15  „  I 

.  10  0 

16  „  I 

.  10  6 

18  „  I 

.  11  0 

16  „  1 

.  11  6 

18  „  1 

8.    d. 

.  11 
.  12 
.  12 
.  16 
.  17 
.  20 
.  22 

Estimates  given  for  large  quantities 
India  Rubber  Washers  for  Packing  Water  Gauges  supplied  to  order. 


FIG.  572. 

FIG.  568. 

FIG.  570. 




£    B.    d. 

Gas  Pressure  Gauge,  with  6 -inch  glass  syphon,  Wood  Scale  divided  to 
inches  and  tenths,  and  brass  mountings 0 

Ditto ditto,  with  Stopcock  0  10 

Ditto,  with  Ivory  Scale  and  Stopcock  (fig.  568),  best  finish  .  0  14 

Gas  Pressure  Gauge,  large  size  (fig.  570),  with  Stopcock  and  Union  1    5 
Ditto,          of    superior  finish,  as    supplied    to    the    Metropolitan 

Board  of  Works,  in  Brass  Mountings,  with  stopcock      ,        .         .  1  10    0 
Gas  Inspector's  Gauge,  with  fittings  complete,  in  leather  pocket 

case  (fig.  572)     ,        ,        .        . -220 



FIG.  565. 

FIG,  575. 

FIG  573. 

£     s.    d. 

573  Steam  Engine  Indicator,  in  gun  metal,  for  ascertaining  the  amount 

of   power  exerted  during  any  part  of  the  stroke,  Low  Pressure 

(fig.  573) 550 

574  Ditto  ditto  .       .       .       .        High  Pressure    660 

575  Richard's  Indicator  with  one  Spring  (fitted  with  Darke's  Patent 

Detent  and  Cord  Adjuster)  fig.  575 8  10    0 

576  Extra  Springs,  ten  varying  scales each    0  10    0 

577  Paper  Cylinder  Spring 016 

578  Arrangement  for  Oscillating  Engines 0  10    0 

579  Metallic  Paper per  packet    040 

580  Treatise  on  Indicator New  Edition    090 

581  Extra  Stop  Cock 080 

582  A  3-way  Cock  for  taking  diagrams  from  top  and  bottom  of  cylinders  without 
shifting  the  Indicator  made  to  order.     Connecting  Pipes  made  to  order.    Elbow 
for  attaching  the  Indicator  to  Horizontal  Engines  made  to  order. 

583  Reducing  Gears,  for  reducing  the  stroke  of  the  Engine  down  to  that  of  the 

Indicator.  Made  to  order. 

584  Small  size  with  Pulleys  for  strokes  varying  from  4  ft.  6  in.  down  to  1  ft,  6  in., 
price,  £4  17s.  6d.,  can  be  attached  direct  to  the  Indicator. 

Larger  size  for  strokes  from  6  ft.  down  to  1  ft.  6  in.,  £5  17s.  6d. 
These    instruments    are    packed    in    mahogany  cases  with  their   necessary 

585  Old  Indicators  (Richard's),  fitted  with  Detent  at      .        .        .        .      1  10    0 

586  Patent  Cord  Adjusters      .       .       .       ....       .       .056 

45,    COBNHILL,    E.C.,    AND    122,    BEGENT    STREET,    W.,    LONDON.  199 

FlG.  578.  FIG.  587*. 

587  The  Patent "  Concentric  "  Steam  Engine  Indicator,  (figs.  587  &  587*)  Negretti 
and  Zambra  call  the  attention  of  Engineers  to  great  improvements  in  the  new  "  Con- 
centric "  Indicator,  which  reduces  the  vibration  of  the  instrument  to  a  minimum. 

The  paper  drum  is  arranged  in  such  a  manner  that  it  revolves  concentrically 
with  the  piston  cylinder.  The  pull  action  is  direct  upon  the  coupling  which 
connects  it  to  the  cylinder  of  the  engine.  This  arrangement  causes  less  vibration 
to  the  instrument  than  if  the  drum  were  fixed  on  an  arm,  as  in  the  ordinary  form 
of  Richard's  Steam  Engine  Indicator. 

A  small  instrument  is  made  especially  for  high  speeds,  to  which  this  indicator 
is  particularly  adapted. 




588  Before  working,  a  sheet  of  metallic  paper  is  placed  around  the  drum,  and  fastened  to  it 
by  means  of  the  two  clips,  The  cord  is  then  attached  to  the  most  convenient  part  of  the 
piston  rod — or  other  part  of  the  engine  working  in  unison  with  it.  The  Indicator  is 
fastened  to  the  cylinder  of  the  engine  by  means  of  the  cock  and  coupling.  The  small 
leading  wheels  may  be  turned  in  any  direction  required.  To  change  the  spring,  unscrew  the 
nut  at  top,  through  which  the  piston  rod  (of  Indicator)  works,  and  by  lifting  the  arm  which 
supports  the  parallel  motion,  the  piston  rod  will  come  out.  The  pencil  can  be  removed  from 
or  pressed  against  the  paper  by  lifting  or  pressing  the  stud  connected  to  the  slotted  bar 
which  the  pencil  works. 

It  will  be  necessary,  in  sending  orders,  to  specify  particularly  the  number  of  springs 
required  and  the  pressure  they  will  have  to  indicate. 

All  the  springs  will  fit  every  instrument,  and  they  can  be  readily  changed  by  any  one. 

The  springs  are  made  to  ten  scales,  as  follows  : 

1     i-in. 




represents  1-lb. 

No.  5 


.       .       • 

15  ,+     60 


on  the  square  in., 


>»     6 


.      « 

15  , 

+     80 





15  to 

+     10 

»»    7 


.        Atmosphere  , 

+    100 

2    ^ 




15  „ 

+     22 

»    8 




+    125 

3      To 

15  „ 

+     35 

„     9 


+   150 

:      "SO 



15  „ 

+     47 

„  10 


.        .        . 

.       „    +    175 


£  s. 
7  10 
0  10 
0  10 



Indicator  with  one  spring,  &c.,  in  box,  fig.  587 

Ditto          ditto,        Smaller  size        .         . 

Extra  Springs  (with  scales)       .         . 

Paper  Cylinder  Spring        ...... 

Arrangement  for  Oscillating  Engines       .        .        . 

Metallic  Paper    .....        per  packet 

Treatise  on  Indicator          .         .         .     New  Edition 

Extra  Stop  Cock         ......        . 

Three-way  Cocks  for  taking  diagrams  from  top  and 
bottom  of  Cylinder  without  shifting  the  Indicator 

Elbow,  for  attaching  the  Indicator  to  horizontal 
Engines        ........ 

Connecting  Pipes  made  to  order. 

Spring  No  1  has  been  specially  adapted  to  indicate  the  vacuum  on  a  large  scale  in 
engines  or  pumps  which  work  at  high  pressures.  The  springs  showing  pressures 
above  80-lbs.  will  be  made  to  indicate  the  vacuum  also  when  so  ordered,  and  springs 
will  be  made  also  to  any  other  scale  desired. 


589    Improved  Engine  Counter,  for  counting  Oscillating  motion,  Reciprocating 



Strokes,  or  Revolutions  in  machines. 

4  figures,  counts  up  to  10,000 

5  „  „  100,000 

6  „  „  1,000,000 

7  „  „         10,000,000 

£    s. 

2  16 

3  10 

4  10 

590  Harding's  Patent  Speed  Indicator.  —  This  instrument  has  been  designed  for 
showing  without  counting  or  the  use  of  a  watch,  by  the  position  of  an  index  on  a  dial, 
the  actual  rate  of  speed  at  which  any  Machine  or  Engine  is  at  any  moment  revolving. 
The  Speed  Indicator  enables  the  Engineer  to  see  at  a  glance  the  variation  in 
the  rate  of  speed  at  which  his  machinery  is  running  and  detect  causes  of  irregularity 
and  run  his  engine  at  normal  speed,  Price,  £5  10  0 

45,   CORNIIILL,   B.C.,   AND    122,    REGENT   STREET,    W.,    LONDON. 



FIG.  A. 

FIG.  c. 

591    The  ease  with  which  the  record  of  these  Counters  can  at  any  time  be  read  off 
is  a  great  advantage  which  they  possess  over  all  dial  counters  (such  as  those  on 
water  and  gas  meters),  in  the  difficult  reading  of  which  important  errors  are  often 

Other  advantages  of  these  Counters  are, — great  simplicity  of  parts  and  solidity 
of  construction,  in  consequence  of  which  it  is  almost  impossible  for  the  apparatus 
to  get  out  of  order. 

It  consists  in  an  ingenious  combination  of  wheels  and  pinions.  Each  number 
wheel  carries  on  the  right  edge  of  its  rim  twenty  teeth,  and  on  the  left  edge  only 
two.  The  pinions  are  provided  with  eight  unequal  teeth,  four  being  as  broad  and 
four  half  as  broad  as  the  pinion.  Thus,  as  each  number  wheel  completes  its  revo- 
lution, it  moves  the  next  one  on  one-tenth,  and  all  the  wheels  are  safely  locked, 
except  at  the  moment  when  they  are  being  moved  forward  by  their  pinions.  Some 
idea  of  the  perfection  of  this  arrangement  may  be  gathered  from  the  fact  that  the 
Pocket  Counter  or  Speedometer,  of  which  the  mechanism  is  a  mere  reduction  of  that 
of  the  large  Counters,  may  be  used  at  speeds  over  5,000  per  minute. 

No  (A)  Large  Engine  Counter,  7  figures,  to  count  to  ten  millions,  with  £    s.    a. 
rotary  or  reciprocating  motion,  and -arranged  so  as  to  readily 
set  back  to  zero  (fig.  A)  .        .        .         .         .        .        .         .     5  10     0 

Square  Engine  Counter,  ten  inches  long,  5  figures 5  10    0 

Ditto  Ditto     with  superior  Clock  lever  movement  for  use  in 

Marine  Engine  rooms.  The  Patent  Enamelled  Number  Wheels 
shew  indelible  black  figures  on  a  white  ground  specially  useful 

in  dark  positions 11  11     0 

No.  (B)  Small  Machine  Counters  (with  rotary  action  only),  with  6  figures    2  10    0 
Ditto  ditto  with  4  figures    330 

No.  (c)  Pocket  Counter  or  Speedometer  (plated,  and  in  handsome  case), 

with  4  figures,  and  steel  friction  bits  (fig.  c)  .        .        .    2  10    0 

No.  (D)  Turnstile  Counters,  5  figures 3  15    0 

Harding's  Improved  Engine  Counters  to  suit  customers'  special  requirements  made  vp  to 
order.    Full  details  should  be  supplied  as  to  what  is  desired. 


592  Duckham's  Patent  Suspended  and  Self  -  Acting 
Weighing  Machines  and  Dynamometers,  adapted  to  the 
Standards  of  all  nations. 

They  are  entirely  self-acting,  and  indicate  the  weight  of 
even  the  most  ponderous  goods,  during  the  ordinary  operation 
|  of  loading  or  unloading. 

They  combine  extreme  simplicity  and  unlimited  power 
I  with  general  utility,  accuracy,  low  price,  and  economy  in 
I  working. 

They  are  invaluable  to  MERCHANTS,  SHIPPERS,  DOCK 
AND  RAILWAY  COMPANIES,  as  a  ready  and  costless  means  of 
ascertaining  the  weight  of  merchandise  in  transit ;  to  IRON- 
MASTERS, that  they  may  ascertain  the  weight  of  material  even 
Fm.  592.  during  the  process  of  manufacture ;  to  CHAIN,  WIRE,  AND 

ROPE  MANUFACTURERS  AND  PURCHASERS,  thab  the  strength  as  well  as  the  weight 
of  such  material  may  be  proved ;  to  SHIP  OWNERS,  that  the  weight  of  cargo  and 
stores  may  be  checked  by  the  simple  operation  of  lifting  the  same  on  board ;  to 
ENGINEERS,  BOILER-MAKERS,  HARD-WOOD  MERCHANTS  ;  and  in  fact,  to  ALL  and 
any  who  deal  with  goods  by  weight,  or  are  interested  in  knowing  the  strength,  of 
materials  or  machinery,  that  the  goods  may  be  weighed,  and  strains  and  strengths 
tested,  by  a  process  which  is  entirely  free  of  expense. 

"  The  inventor  provides  an  open-top  cylinder,  which  is  filled  with  water  or  oil, 
and  fitted  with  a  piston  and  pressure  gauge.  For  the  purpose  of  weighing  goods 
the  cylinder  is  slung  from  an  ordinary  crane  hook.  The  goods  are  attached  to  the 
piston  rod,  and  immediately  these  are  lifted  as  in  process  of  loading  or  unloading 
ships  or  wagons  the  weight  is  denoted  on  the  dial.  Nothing  can  be  more  simple." — 
Mechanic's  Magazine. 


£    B.   a. 

12  cwt.  to  3  tons  capacity,  45  Ibs.  weight 17  17    0 

5  tons  ditto  56  „ 24    0    0 

10  tons  ditto  85          „ 30    0     9 

30  tons  ditto  280          „          .         .        .         .        .        50    0    0 

593  Hearson's  Strophe-meter,  or  Revolution  Indicator.  This  Instrument  indi- 
cates, by  means  of  a  pointer  on  a  marked  dial,  the  number  of  revolutions  per  minute 
an  Engine  is,  at  the  time,  revolving. 

It  is  so  designed  that  when  Engines  are  subject  to  incessant  momentary 
fluctations  of  speed,  the  needle  points  steadily  at  a  number  expressing  the  mean 

It  will  be  found  particularly  useful  for  Locomotives  (the  dial  being  graduated 
in  miles  per  hour),  for  Spinning  Machinery,  and  for  Ships. 

The  Instrument  is  worked  by  means  of  a  rope  passing  round  a  pulley  on  the 
shaft  of  the  Engine,  or  in  connection  with  a  friction  roller  against  a  coupling  of 
the  shaft. 

For  description  of  the  Instrument  see  paper  read  at  the  Institute  of  Naval 
Architects,  and  published  in  the  Transactions  for  1874,  and  also  article  in  No.  4 
Annual  of  Royal  School  of  Naval  Architecture. 


£     s.     d. 

Strophometer  with  9-inch  Dial 10  10    0 

Leading  Pulleys  for  ditto 036 

Connecting  Arrangements  for  ditto  ....         from          2  10    0 

45,    CORNHILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,    LONDON. 


594  Gauntlett's    Pyrometer.  —  This    Pyro- 
meter is  constructed  of  metal  bars  expanding 
in  a  different  ratio  upon  the   application  of 
heat,  by  which  can  be  ascertained  tempera- 
tures above  the  range  of  the  mercurial  ther- 
mometer.    Its  form  is  that  of  a  long  tube, 
surmounted  by  a  dial  with  an  index  or  pointer 
to  indicate  to  300°  for  fluids,  or  to  1,009°  for 
furnaces,  ovens,  &c.  (fig.  594)  .... 

595  Chronometrical      Pyrometer    Thermo- 
meter (Gauntlett's),  with  8-day  time-piece  to 
indicate  to  300°  or  1,009°          . 

596  Daniell's  Pyrometer,  for  indicating  high 
temperatures,  such  as  the  melting  point  of 
metals,  temperature  of  furnaces,  &c.,  by  the 
expansion  of  a  bar  of  Platinum  enclosed  in  a 
black  lead  cylinder,  and  measured  by  an  index 
arranged  with  a  spring  and  lever,   to  show 
upon  a  divided  arc  very  small  changes     . 

597  Wedgwood's     ditto,     for     the     same 
purpose,  by  the  expansion  of  a  Cylinder  of 
earthenware      ...... 

£     3     d. 


8  10    0 



598  Ferguson's  ditto,  for  showing  the  differ- 
ence of  expansion  in  metals,  suited  for  the 
lecture  table  as  an  experimental  instrument  .550 

599  Hydro  Pyrometer,  Captain  O.  Bystrom's  (Swedish 
Artillery),  for  ascertaining  the  heat  of  furnaces,  &c. 
A  ball  of  platinum,  or  other  metal,  is  arranged  upon  a 
metal  rod  in  such  a  manner  that  it  can  be  inserted  into 
the  furnace  to  be  tested,  and  when  heated  equal  to  the 

FIG.  594.  temperature  of  the  furnace  quickly  withdrawn  and 
dropped  into  a  given  quantity  of  water.  By  observing  the  temperature  of  the  water 
before  and  after  the  above-mentioned  procedure,  the  difference  obtained  will  be  th^ 
value  or  amount  of  heat  of  the  furnace 1  15  0 

This  Pyrometer  is  the  most  simple  and  practically  useful  of  any  of  the  above  at 
very  high  temperatures.  Price  for  Thermometer,  Copper  Bolt  and  Wooden 
Water  Vessel. 

Further  details  respecting  Pyrometers    will    be  given  in    our    section    on" 
Chemical  Apparatus. 





600  The  PYROMETER  is  shown  in  figs.  1  and  2  in 
margin  (fig.  1  being  a  vertical,  and  fig.  2  a  horizontal 
section),  and  consists  of  a  copper  vessel  capable  of 
holding  rather  more  than  a  pint  of  water,  and  well 
protected  against  radiation  by  having  its  sides  and 
bottom  composed  of  a  double  casing,  the  inner  com- 
partment of  which  is  filled  with  felt.  A  mercury 
thermometer,  b,  is  fixed  in  it,  having,  in  addition  to 
the  ordinary  scale,  a  small  sliding  scale  c,  graduated 
and  figured  with  50  degrees  to  1  degree  of  the 
thermometer  scale ;  6  solid  copper  cylinders  are 
provided  with  the  Pyrometer,  each  accurately 
adjusted  in  size,  so  that  its  total  capacity  for  absorb- 
ing heat  should  be  l-50th  that  of  a  pint  of  water. 

In  using  the  Pyrometer,  a  pint  (0*568  litre,  or 
34'66  cubic  inches)  of  water  is  measured  into  the 
copper  vessel,  and  the  sliding  pyrometer  scale  c  is 
set  with  its  zero  at  the  temperature  of  the  water  as 
indicated  by  the  mercury  thermometer  b ;  a  Copper 
Cylinder  d  is  then  put  into  the  furnace  or  hot  blast 
current  the  temperature  of  which  it  is  wished  to 
ascertain,  and  is  allowed  to  become  heated  for  a  time 
varying  from  2  to  10  minutes  according  to  the 
intensity  of  the  heat  to  be  measured. 

It  is  then  to  be  withdrawn  and  quickly  dropped 
into  the  water  in  the  copper  vessel,  where  it  raises 
the  temperature  of  the  water  in  the  proportion  of 
1°  for  each  50°  of  the  temperature  of  the  copper.  The 
rise  of  the  temperature  may  then  be  read  off  at  once 
on  the  pyrometer  scale,  and  if  to  this  is  added  the 
temperature  of  the  water  as  indicated  on  the  mercury 
thermometer  before  the  experiment,  the  exact  tem- 
perature required  is  obtained. 

For  very  high  temperatures  Platinum  cylinders 
may  be  employed  instead  of  Copper. 

Price  of  Siemens'  Water  Pyrometer,  with  Thermometer  and  six  copper 
cylinders,  complete £440 

Water  Pyrometer,  with  Thermometer  and  six  wrought-iron  cylinders, 
complete  .  .  .  .  ,  .  .£400 

45,   CORNHILL   E.G.,   AND    122    REGENT    STREET,   W.,    LONDON.  205 

FIG.  602. 

Gauges  of  any  Pressure  not  exceeding  300  Ibs.  per  square  inch,  SQQfeet  of  water, 

and  Vacuum  Gauges : 


601  For  Portable  Engines,  Brass  Case.    4-inch  with  wire  £   *.    a. 

guard '  1  15    0 

602  No.  1.    In  Metal  Case,  with  Brass  Rim           6-inch  dial  226 
No.  2.    In  Brass  Case      .       .       .  (fig.  602)         „  2  10    0 

603  No.  3.    In  Metal  Case,  with  Brass  Rim          7  276 
No.  4.    In  Brass  Case    ....                 „  2  10    0 

604  No.  1.    Patent  Steel  Tube  Metal  Case,  with  Brass  Rim, 

above  300  Ibs.  up  to  1,000  Ibs.        .        .        6-inch  dial  2  15    0 

605  No.  2.    Ditto  Brass  Case,  above  300  Ibs.  up 

to  1,000  Ibs 6  330 

606  12-Inch  with  Transparent  Dial  for  Dark  Engine  Rooms, 

Metal  Case,  with  Brass  Rim 330 

507    Combined  Pressure  and  Vacuum  Gauges,  at  a  slight  increase  of  these  prices. 

608  Hydraulic  Gauge,  above  1,000  Ibs.  up  to  10  tons,  with 

Maximum  Pointer    and   loose  nuts    for  connecting 

10-inch  Dial  550 

Ditto  ditto       ....         6-inch  Dial  4  10    0 

Ditto  ditto  to  4  Tons      .  ...  400 

For  each  additional  ton,  5s.  extra.     Maximum  Finger  applied  to  any  gauge,  10s.  extra. 

609  Dynamometer,  Schaffer's.    The  dial  showing  the  weight  is  accurately  divided, 
by  applying  dead  weight.     Two  solid  curved  steel  bars  act  as  springs.     Weight  or 
strain  applied  has  the  tendency  to  straighten  these  springs,  and  the  slightest  motion 
of  the  same  is  multiplied  and  transferred  by  a  suitable  arrangement  to  a  pointer 
which  indicates  the  correct  weight  on  the  dial.     Two    strong  rods  outside   the 
springs,  moving  loosely  in  their  joints,  act  as  safeguards  in  case  the  springs  break. 

Price,  up  to  20  tons        .        .        £25    0    0 

*  Schaffer't  Gauges,  Sfc.,  not  kept  in  stock,  but  are  supplied  to  order. 



FIG.  4. 

FIG.  5. 

FIG.  2. 

FIG.  7. 

FIG.  8. 

FIG.  6. 

FIG.  1.  FIG.  9.  FIG.  3. 


35,    CORN11ILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,    LONDON.  207 

610  PRICES    FOR 



TEADE    U  -,  MAEK. 

Gauges  not  bearing  above  Trade  Mark  are  not  of 
M.  Bourdon's  Manufacture. 

Diameter  of 


Figs.  3  and  7. 

Figs.  4  and  8. 


Eccentric  Hand. 
Figs.  2  and  6. 


Figs.  1  and  5. 

10  inches. 
7      „ 
6       „ 
5       „ 
4       „ 
3      „ 

5  inches. 

No.  0 

No.  3 
No.  5 
No.  8 
No.  7 
No.  6 

£2  18     0 
1  16     0 
1  14    0 


No.  4 
No.  50 
No.  8c 
No.  70 
No.  60 

1  18     0 
1  10     0 

1  18    0 
1  10    0 
1     7    0 

£3  13    0 
1  14    0 
1  12    0 
1  10    0 

Above  Gauges  in  round  cases  of  polished  brass  with  Or  without 
flange,  graduated  to  all  pressures  up  to  300  Ibs.  per  square  inch,  and 
fitted  with  gun-metal  cocks  and  union  complete. 

Gauges  above  300  Ibs.  per  square  inch  are  without  cocks. 

No.  2,  Fig.  9,  Oblong  Iron  case  (9x6  in.)  with  connecting  screw  joint, 
each,  £160 

Above  prices  are  for  all  pressures  up  to  300  Ibs.  per  square  inch.  From  300 
to  1,400  Ibs.  pressure  per  square  inch  there  will  be  an  additional  charge  of 
Two  Shillings  for  every  100  Ibs.  above  300  Ibs. 

Cocks  for  5  in.,  7  in.,  and  10  in.  Gauges,  for  pressure  above  300  Ibs.  per  square 
inch,  up  to  1,400  Ibs.  will  be  Twelve  Shillings  each. 





FIG.  14. 

FIG.  10.  FIG.  11. 


FIG.  12. 

FIG.  16.  FIG.  13.  FIG.  15. 



FIG.  18.  FIG.  17. 


45,    COBNHILL,    E.G.,   AND    122,    EEGETNT    STEEET,    W.,    LONDON.  209 


With  Central  Hands,  divided  from  300  Ibs.  up  to  5  tons  per  square  inch. 


Screw  Joint. 
Fig.  10.    - 

Fig.  11. 

With  Valve, 
Union,  and 

With  Valve, 
Union,  and 





10  inch. 

7     „ 
5     „ 

2  10     0 

£4  10    0 
3  10    0 
2  16     0 

£5  10     0 






Cocks  for  above  Gauges  (if  required)  30s.  each,  extra. 


Used  by  Inspecting  Engineers  for  Testing  Gauges  and  Boilers. 

Fig.  12.  Pocket  Standard  Gauge,  with  open  face,  in  polished 
brass  case,  engraved  dial,  graduated  to  300  Ibs.  per 
square  inch,  in  morocco  case  and  clamp  screw  each 

Fig.  13.  Two  Gauges  as  the  preceding,  but  fixed  on  the  same 
union  and  in  a  mahogany  box  .  .  .  per  pair 

Fig.  14  Pocket  Standard  Duplex  Gauge,  in  polished  brass 
case  (5  inches  diameter)  engraved  dial  graduated  to 
300  Ibs.  per  square  inch,  in  Leather  case  with  clamp 
screw  ........  each 

Fig.  15.  Standard  Duplex  Gauge,  with  two  concentric  hands, 
polished  brass  case,  graduated  to  300  Ibs.  per  square 
inch,  with  gun-metal  cock  ....  each 

Fig.  16.  Standard  Duplex  Gauge,  with  independent  hands, 
&c.,  as  last 


3  inches.  5  inches. 

3    0 

7  inches. 

3  16     3 

7  13    0 

6    5    0 

10  inches. 


3  14    0        4  15    0 


Diameter  of 

or  Minimum 

Second  Scale 
of  Feet  of 
Water  or 

For  3-way 

Writing  Name 
on  Dial. 

Open  Face 






10  inch. 

s.    d. 

s.    d. 

s.    d. 

s.    d. 

B.    d. 

7     „ 

10     0 

5     0 

2     0 

1     0 

10    0 

6     ,, 

7    0 

5     0 

2     0 

1     0 

10    0 

5     „ 

7    0 

5     0 

2     0 

1     0 

8    0 

4     „ 

5     0 

3     0 

2     0 

1     0 

8     0 

3     „ 

5     0 

3     0 

2     0 

1     0 

8     0 

5     0 

3     0 

2     0 

1     0 

8    0 



Fig.  17.  Bourdon's  Registering  Gauge,  in  japanned  case,  graduated  to 
100  Ibs.  per  square  inch,  with  gun-metal  Cock  and  Union,  and  100  printed 

cards £7  15  0 

Extra  cards,  (if  required)  per  100 080 

Fig.  18.  Bourdon's  Double  Gauge,  to  be  set  in  Engine-rooms,  and  showing 
on  the  same  dial  (10  inches  diameter),  pressure  of  Steam  in  the  Boiler, 
and  the  amount  of  Yacuum  in  the  Condenser,  Polished  brass  case,  and  two 
Cocks  with  Union  .  £600 

*  A  Table  of  Hydraulic  Pressure  will  be  found  in  the  Appendix. 



FIG.  24. 

FIG.  20.     FIG.  21. 

FIG.  19. 

FIG.  23.     FIG.  22. 


Fig.  19.  Connecting  Screw  Joint 

Figs.  20  &  21.  Gun  Metal  Cock 

Figs.  22  &  23.  Three-way  Cock  for  Standard  Test  Gauges 

Fig.  24.  Iron  Syphon,  with  Union  .... 

Fig.  24.  Copper  Syphon,  with  Union 


each    0 

s.    d. 

1     6 


Purchasers  are  desired  to  examine  and  compare  M.  Bourdon's  Gauges.  They 
will  find  the  works  to  be  constructed  and  finished  like  a  watch,  whilst  the  majority 
of  imitations  are  put  together  ROUGH  FROM  THE  CASTINGS,  consequently  liable  to 
adhere  and  give  erroneous  indications. 



Gun-metal  Steam  and  Water  Taps  of  all  sizes  and  shapes,  Safety  Valves,  Steam 
Whistles,  Gauge  Taps,  High  Pressure  Water  and  Steam  Yalves,  Gas  Yalves,  Boiler 
Fittings  of  all  kinds,  Feed  Pumps  and  Valves,  Wrought  Iron  Steam,  Gas,  and 
Water  Tubes,  Boiler  Tabes,  Hand  Force  Pumps,  Fire  Engine  and  Brewery  fittings, 
Pump  fittings,  Caps  and  Screws  of  every  form,  Hydraulic  Presses  and  Force 
Pumps,  Hydraulic  Rams  of  various  sizes  and  construction,  Turning  Lathes  and 
Tools,  Portable  Forges  and  Smiths'  Tools,  &c.,  &c.,  Fencing  Wire,  Railway  Metal 
Bars,  Tools  and  appliances  of  all  kinds  supplied  to  order  by  Negretti  and  Zambra, 
of  the  very  best  manufacture. 

Foreign  Correspondents  sending  particulars  of  their  requirements  to  Negretti  and 
Zambra  may  rely  upon  thepersonal  attention  of  the  Firm  in  carrying  out  commissions 
entrusted  to  them  in  this  special  branch  of  their  Shipping  Business. 

At  pages  95  to  110,  will  be  found  Anemometers  for  testing  Yentilating  or 
Furnace  Shafts  and  Wind  Pressure,  Recording  Anemometers,  and  Tide  Gauges,  &c. 

45,    CORNHILL,    B.C.,    AND    122,    REGENT    STREET,    W.,    LONDON. 



FIG.  617. 

617  Improved  Combined  Portable  Steam  Engine  and  Boiler.  These  Engines  are 
fitted  with  governor,  throttle  valve,  safety  valve,  feed  pump,  water  and  steam  gauge, 
&c.,  &c.,  complete,  ready  for  immediate  use.  Recommended  for  simplicity  and 
economy ;  well  suited  for  Exportation. 

Consumption  of  fuel,  7£  Ibs.  of  coal  j  per  horse  power, 
1  cubic  foot  j        per  hour 


Ditto      ditto 

*  Horse  Power  Cylinder.  Diameter. 
2  „  4-in. 

4  5l-in. 





5-ft.  0-in. 


2-ft.  4-in. 

£73    0    0* 

5-ft.  6-in. 

2-ft.  4-in. 

85    0    0* 

7-ft.  0-in. 

2-ft.  4-in. 

105    0    0 

8-ft.  0-in. 

2-ft.  8-in. 

165    0    0 

*  2  and  3,  if  not  fitted  with  Governors,  less  £5. 

The  fly-wheel  shaft  is  made  sufficiently  long  to  admit  of  a  drum  being  fixed  on 
if  required,  which  can  be  supplied  (to  any  diameter  ordered)  along  with  the 
Engine,  at  an  extra  cost  according  to  size. 

The  above  Engines  occupy  a  very  small  space,  and  will  be  found  admissible 
in  places  where  no  other  form  of  engine  and  boiler  could  be  fixed.  They  are  con- 
structed in  an  exceedingly  substantial  and  simple  manner,  every  part  being 
perfectly  easy  of  access,  and  consequently  can  be  readily  understood  and  managed. 

The  boilers  are  fitted  up  with  strong  welded  tubes  (varying  in  number 
according  to  the  size  of  the  boiler),  intersecting  the  fire-box,  and  a  mud  hole  is 
placed  opposite  each  tube,  for  the  purpose  of  cleaning  them  out.  They  are  tested 
up  to  200  Ibs.  pressure  to  the  square  inch. 

The  foundation  plate  answers  the  purpose  of  feed  water  tank,  in  which  the 
water  is  heated  before  passing  into  the  boiler ;  and  also  of  an  ashpit. 

No  brickwork  or  foundation  is  required. 

N.  and  Z.  will  forward  special  quotations  to  Foreign  Correspondents  for  Steam 
and  Gas  Engines  or  other  Machinery  upon  receiving  details  of  the  nature  and  amount 
of  work  to  be  performed. 

p  2 



THE  science  of  .Optics,  which  consists  in  the  examination  of  the  phenomena  of  light 
and  vision,  is  one  of  the  most  important  and  most  useful  branches  of  physical 
science.  By  the  aid  of  its  appliances  we  are  permitted  to  obtain  a  glimpse' of  the 
immensity  of  the  universe,  and  are  enabled  to  reveal  wonders  of  creation,  of  which 
but  for  this  power  granted  to  us  we  should  be  in  perfect  ignorance.  By  means  of 
the  Telescope  we  are  made  acquainted  with  the  existence  of  spheres  and  worlds 
floating  in  boundless  space,  illustrating  in  the  most  sublime  manner  the  perfect 
harmony  that  exists  in  the  motions  of  the  heavenly  bodies. 

The  Microscope  affords  an  insight  into  the  minute  structure  of  animal  and 
vegetable  life,  and  discloses  to  the  wondering  spectator  forms  of  life,  the  variety 
and  beauty  of  which  display  in  the  most  convincing  manner  the  infinite  power  of 
the  Great  Creator. 

But  of  all  the  gifts  which  science  has  so  freely  lavished  on  humanity,  and  all 
tending  to  its  benefit  and  improvement,  perhaps  there  is  none  that  can  rank  higher 
than  the  means  afforded  of  assisting  the  natural  vision,  and  of  enabling  us  to  correct 
in  a  most  simple  and  perfect  manner  the  irregularities  of  sight,  which  are  conse- 
quent on  alterations  silently  going  on  in  the  structure  of  that  wonderful  and  deli- 
cately constructed  organ,  the  Eye.  The  sight  has  in  all  time  been  justly  accounted 
the  greatest  of  blessings,  and  it  deserves  our  strictest  attention  in  order  that  the 
advantages  of  it  may  not  be  lost  to  us  at  an  earlier  period  than  is  absolutely 
necessary  from  physical  decay. 

Those  beginning  to  require  the  aid  of  Spectacles  are  obliged,  before  distinct 
vision  can  be  obtained,  to  hold  the  candle  or  to  have  the  source  of  light 
between  the  eye  and  the  book  they  read,  in  order  to  force  the  pupils  of  their  eyes 
into  a  proper  state  of  contraction,  that  they  may  see  distinctly  the  characters 
before  them.  Now  this  is  a  state  of  things  that  should  never  occur,  for  if  indulged 
in,  and  the  eye  be  tampered  with,  it  will  eventually  lead  to  great  impairment  of 
vision.  The  power  of  adjustment  in  the  eyes  varies  exceedingly  in  different 
individuals  and  also  at  different  periods  in  the  life  of  each  person ;  being  strongest 
in  youth,  and  gradually  diminishing  with  advancing  years. 

From  this  circumstance  it  is  easy  to  see  the  reason  of  the  fatigue  caused  by 
the  strain  on  the  ciliary  process  of  the  eye  in  bringing  it  to  a  proper  adjustment 
for  objects  at  different  distances,  and  an  individual  who  has  habitually  to  make  an 
effort  to  adjust  his  eye  to  these  variations  of  circumstances,  should  lose  no  time  in 
applying  to  the  Optician  to  obtain  assistance  from  the  use  of  glasses. 

From  what  we  have  said  above,  let  it  not  be  supposed  that  the  indiscriminate 
use  of  Spectacles  is  recommended ;  very  far  from  it.  We  must,  before  resorting 
to  Spectacles,  ascertain  the  nature  of  the  defect  in  the  visual  organs,  and  then 
have  the  amount,  and  only  the  exact  amount  of  correction  applied ;  just  in  the 
same  manner  as  with  a  telescope,  we  are  obliged  to  draw  out  the  eye-tube  until 
a  perfect  image  appears  in  the  field  of  view,  nothing  more  or  less  will  suffice  to 
this  end. 





N.  &  Z.  devote  especial  care  and  attention  to  Oculists'  Prescriptions,  and  no 
advance  in  prices  is  made  unless  extra  deep  lenses,  Cylindrical  lenses,  or  Prisms 
are  ordered.  N.  &  Z.  cannot  specify  within  the  limits  of  this  List  the  various 
combinations  which  influence  the  price,  but  if  desired,  the  price  may  always  be 
ascertained  before  ordering. 

The  greatest  care  taken  that  the  Pebble,  or  Glass  Lenses,  are  correctly 
worked  and  polished,  as  well  as  carefully  tested  and  suited  to  the  sight  of  the 
Purchasers,  and  also  that  the  Frames  are  formed  to  fit  the  face. 




FIG.  61 

FIG.  618*. 

£    a. 

£    s.    d. 

Fine  Blue  or  Bronzed  Steel  Spectacles,  with  straight  or 

turn  pin  sides  (figs.  618  and  618*)          .        .        .        .     0  10    6  0  12 

Ditto  ditto  ditto,  with  Pebbles     .  15s.     0  17     6  11 

Fine  Blue  or  Bronzed  Steel  Spectacles,  with  straight  or 

turn  pin  sides  (figs.  618  and  618*),  extra  large  lenses  .     0  12     6  0  15 

Ditto  ditto  ditto,  extra  large  Pebbles  .  1     5 

Blue  Steel  Spectacles,  with  straight  sides  (fig.  618)       .026  03 

Blue  or  Bronzed  ditto  ditto 056  07 

Cataract  Spectacles,  in  various  mountings      .    10s.  6d.    0  15    0  11 
Cataract  Spectacles  are  mostly  made  specially  to  meet  the  requirements 

of  the  Patient. 



FIG.   019. 

FIG.  619' 





£      s. 

0  10 

1  1 

619  The  Patent  Pantoscopic  Spectacles  are  so  constructed  as  to  enable  the  wearer 
to  read  or  write  with  comfort.     When  the  Spectacles  are  on  the  face,  the  position 
of  the  lenses  is  such  that  the  light  passes  through  them  at  right  angles  to  their 

urfaces,  and  the  upper  part  of  the  lenses  being  slightly  straightened,  enables  the 
earer  to  converse  with  anyone,  or  see  distant  objects,  without  looking  through 
he  lenses  or  drawing  the  Spectacles  down  upon  the  face,     Figs.  619  and  619*. 
N".  &  Z.  strongly  recommend  this  form  of  Spectacles. 

620  Patent  Pantoscopic  Spectacles,  in  light  blue  steel,  for    £  Es?h'a. 

ladies  or  gentlemen,  with  the  best  Periscopic  Lenses 

Ditto         ditto,  with  best  Brazil  Pebbles          .         .         .     0  15     6 

Ditto        ditto,  in  Solid  G-old,  with  best  Brazil  Pebbles 

42s.     2  10    0 

Ditto        ditto,  in  Solid  Silver,  with  ditto  .110 

Invisible  Steel  Spectacles,  blue  or  bronzed,  with  straight  sides. 

The  lenses  are  grooved  to  receive  the  frame,  which,  being  extremely 
light,  is  scarcely  visible.  These  Spectacles  are  specially  adapted  for  Concave 
lenses  worn  by  short-sighted  persons.  Straight  or  turn  pin  sides 

10s.  6d.,     12s.  6d.,     15s. 

Ditto        ditto        ditto,    with  Pebbles  .        .        .  15s.    0  18    0        150 

Invisible  Steel  Spectacles,  with  Curled  sides  to  fit  behind 
the  ears  (fig.  626) 10s.  6d.    0  12    6        0180 

Ditto        ditto        ditto,    with  Pebbles  .        .        .  15s.    0  18    0        150 




Gold  Spectacles,  fitted  with  Pebbles,  Light  Frames  :— 

10  Carat.         12  Carat.  15  Carat.         18  Carat. 

Single  Sides       £1    7s.  6d.          £1  17s,  6d.  £2  12s.  6d.            £3  15s.  Od' 

Turn  Pin  do.     £1  11s.  6d.          £2    4s.  Od.  £3    Os.  Od.            £4    5s.  Od. 
Ditto    ditto    ditto,  Strong  Frames  : — 

Single  Sides        £1  Us.  6d.          £2    8s.  Od.  £3  Os.  Od.            £4  4s.  Od. 

Turn  Pin  do.       £1  17s.  6d.          £1  12s.  6d.  £3  7s.  6d.             £5  Os.  Od. 
Ditto     ditto     ditto,  Extra  Stout  Frames  .— 

Single  sides        £2  2s.  Od.            £2  15s.  Od.  £3  15s.  Od.            £5    Os.  Od. 

Turn  Pin  do.      £2  5s.  Od.            £3    3s.  Od.  £4 10s.  Od.            £5  15s.  Od. 

631     Either  of  the  above  Spectacles  may  be  had  with  Patent  Pantoscopic  Frames 
without  extra  cost,  as  Fig.  619. 



45,    COfliniILL,    E.G.,    AND    122,    REGENT   STREET,    W.,    LONDON.  215 

FIG.  626. 

632  Invisible  Gold  Spectacles,  with  Curled  Sides  to  fit  behind  the  ears. 

The  lenses  grooved  to  receive  the  frame  (as  Fig.  626),     12  Carat, 
with  glasses  £1  to  £2,  with  Pebbles,  £2  to  £2  10s. 

N.  &  Z.  do  not  recommend  a  higher  quality  gold  for  these  Spectacles,  it  being 
too  soft  for  durability. 

633  Sterling  Silver  Spectacles— 

12s.  6d.  15s.  £1,     and  upwards,  according  to  weight. 

634  Ditto  ditto,    with  Pebbles,         18s.        £1  Is.        £1 5s. 

Gold  and  Silver  Spectacles  are  strongly  recommended  to  persons  residing  in 
Tropical  Climates,  or  at  the  Seaside,  as  they  resist  the  action  of  moisture. 

635  Gold  Double  Eye  Glasses,  (folding). — The  frames  and  the  springs  are  of 

Gold  throughout,  and  with  shell  placquets  to  those  parts  which  touch  the 
nose.    Fitted  with  Pebbles. 

Light  Frames : — 

10  Carat.  12  Carat.  15  Carat,  18  Carat. 

Figs.  640*  &  640f    £1  Is.  Od.  £1 10s.  Od.  £2  2s.  Od.  £2  10s.  Od. 

Fig.  640  £1  5s.  Od.  £1  15s.  Od.  £2  5s.  Od.  £3    Os.  Od. 

Strong  Frames  : — 

Figs.  640*  &  640      £115s.  Od.  £2    Os.  Od.          £2  10s.  Od.          £3  5s.  Od. 

Fig.  640  £2    Os.  Od.  £2    7s.  6d.          £3    3s.  Od.          £4  Os.  Od. 

Fig.  646  £2    2s.  Od.  £2 10s.  Od.          £3    5s.  Od.          £4  4s.  Od. 

Extra  Stout  Frames  : — 

Figs.  640*  &  640    £2    5s.  Od.  £3    3s.  Od.          £3  15s.  Od.          £4  15s.  Od. 

Fig.  644  £2 15s.  Od.  £3  10s.  Od.          £4    4s.  Od.          £5  10s.  Od. 

Fig.  646  £3   3s.  Od.  £4    Os.  Od.          £5    Os.  Od.          £6    6s.  Od. 


FIG.  636.  ^=s^  FIG.  636*. 

636  Gold  Double  Eye  Glasses  (folding),  with  round  or  oval  eyes,  with  Pebbles. 

(Figs.  636  and  636*). 

Strong  Frames  :— 

10  Carat.  12  Carat.  15  Carat.  18  Carat. 

£2  5s.  Od.  £2  15s.  Od.  £3  15s.  Od.  £4  15s.  Od. 

Extra  Strong  Frames  : — 
£2  10s.  Od.  £3  3s.  Od.  £4  Os.  Od.  £5  10s.  Od. 

637  Ditto        ditto        ditto,    with  Spring  and  Catch,   round  or  oval  eyes,  with 

Pebbles,  (Figs.  636  and  644).    Extra  Strong  Frames  :— 

£2  15s.  Od.  £3  10s.  Od.  £4  5s.  Od.  £5  15s.  Od. 

638  Ditto        ditto        ditto,      with  Rigid  Bridge,  folding,  but  used  open  and 

held  in  the  hand.    Round  eyes  only,  with  Pebbles  (Fig.  636°). 

Extra  Stout  Frames  : — 

£5  15s.  Od.  £4  4s.  Od.  £5  5s.  Od.  £6  6s.  Od. 

FIG.  640.  FIG.  640*. 




Blue  or  Bronzed  Steel  Double  Eye  Glasses  (Fig.  640*)    .0 
Best  Nickel  Plated  Steel  Ditto  ditto  (Figs.  640  and  640f) 
having  Shell  Placquets  to  those  parts  which  touch 
the  nose  .....        .        .         .      5s.  6d.     0 

£    s.    d. 


£    s.     d. 


641    Ditto 


ditto,  with  Pebbles  .    12s.  6d.    0  15 

0  10 

1  1 

45,    GORNHILI,    B.C.,    AND    122,    BEGENT    STREET,    W.,    LONDON. 


Each.  Each. 

£    s.    d.  £    a.    d. 

642  Best  Nickel  Plated  Steel  (Figs.  640  and  640*),  highly 

finished  invisible  frames,  with  Grooved  lenses     .        .    0  10    6        0  12    6 

643  Ditto  ditto  ditto    with  Pebbles    .        .    15s.    0  18    0        150 

FIG.  650. 

FIG.  646. 

FIG.  644. 

644    Tortoise-shell  Double  Eye  Glasses  [(Pig.  644)  Round 

or  Oval  7s.  6d.    0  10    6 

645    Ditto 


ditto,     with  Pebbles 

646    Tortoise  SheU   Double   Eye  Glasses  (Fig.  646),  with 
Solid  Steel  Bridge 


12s.  6d.    0  15    0 

12s.  6d.    0  15    0 

ditto,  with  Pebbles      .       .       .110 
ditto,  with  Solid  Gold  Bridge      .150 

ditto,  with  Pebbles      .       .       .    1  10    0 
ditto  (Fig.  650),  Bound  or  Oval 

.  7s  6d.    0  10    6 

0  12     6 

0  17    0 

0  17    6 

1  10    0 
1  15    0 

647  Ditto 

648  Ditto 

649  Ditto  ditto 

650  Ditto  ditto 

Eyes    .        .        .        ' 7s  6d.    0  10    6        0  12    6 

651  Vulcanite  Double  Eye  Glasses  (shape  as  Figs.  644  and  650) 

2s.  6d.    3s.  6d.    0    4    6        056 

652  Figs.  640,  to  650  show  recent  improvements  in  Clip-Nose,  (Pince-Nez) 
Spectacles,  or  Folders.  The  Cushions,  or  Placquets,  on  th'e  inner  edges  of 
the  Frame  distribute  the  pressure  over  a  large  surface,  causing  the  Folder 
to  fit  exceedingly  firm  on  the  face,  and  parallel  to  the  eyes.  These  forms  of 
Folders,  known  as  Chinese,  Japanese,  American  Extension,  or  Non-Pressure, 
are  found  to  be  the  most  comfortable  in  wear  yet  introduced. 




FIG.  653. 

FIG.  654. 

FIG.  657. 

653  Gold  Eye  Glasses,  single  (fig.  653),  fitted  with  Pebbles  Each.             Each. 

i  for  short  sights,  according  to  quality  and  substance  £     s.     d.         £   s.   d. 

10s.  6d.  0  12    6        0  15    0 

654  Gold  Eye  Glasses,  single  (fig.  654),  fitted  with  Pebbles 

for  long  sights,            ditto                ditto,         21s.,  30s.  200         2  10     0 

655  Shell  Rim  Eye  Glasses,  (fig.  653),  fitted  with  Convex  or 

Concave  glasses 2s.  0    2     6        036 

656  Ditto        ditto        ditto,  (fig.  654),  fitted  with  Convex  or 

Concave  glasses 3s.  6d.  0    5     6        0  10    6 

657  Rimless  Eye  Glasses,  (fig.  657),  Concave  or  Convex  glass  010 

658  Ditto    ditto     ditto,  Meniscus  Concave  or  Convex  glass  016        026 


FIG.  A. 

FIG.  B. 

FIG.  C. 

FIG.  D. 


Gold  Hand  Spectacles  (folding),  with  Spring  Joints,  richly  engraved, 
chased,  enamelled  or  inlaid  ;  fitted  with  Pebbles  for  long  or  near  sights — 
10  Carat,  £4  4s.;  12  Carat,  £5  5s.,  £5  10s.,  £6  6s.;  15  Carat,  £6  6s., 
£6  10s.,  £7  7s. ;  18  Carat,  £7  7s.,  £8  8s.  and  upwards  (figs.  A,  B,  C,  D). 

660  Silver    Gilt  ditto    ditto    ditto,    fitted    with    Pebbles 

(figs.  A,  B,  C,  D) 40s.,  45s.    2  10    0        330 

661  Tortoise-shell  or  Mother-o'-Pearl  Fronts,  with  Silver-gilt 

settings,  fitted  with  Glasses  .  18s.,  21s.,  25s.     1  10    0        200 

45,    CORNHILL,    B.C.,    AND    122,    EEGENT    STREET,    W.,    LONDON. 









FIG.  663. 

£    s.    d. 

£    s.    d. 

Best   Solid   Steel    Frame    Eye   Protectors    or   Dust 

Spectacles,  (fig.  662)  with  wire  gauze  or  crape  cups, 

and  fitted  with  smoke  or  blue  tinted  flat  glasses   of 

the  finest  quality 10s.  6d.     0  15     0 

Best  Solid  Steel  Frame  Eye  Protectors,  (fig.  663)  with 

wire  gauze  cups,  and  fitted  with  large  smoke  or  blue 

tinted  Cup  Shaped  or  Spherical  Glasses  of  the  finest 

quality 10s.   6d.     0  15     0 

Best  Steel  Spectacles,  (fig.  663),  fitted  with  large  smoke 

or  blue  tinted  spherical  -glasses  of  the  finest  quality 

10s.  6d.    0  12    6        0  15    0 
Ditto  ditto,  fitted  with  large  smoke  or  blue 

tinted  spherical  glasses 7s.  6d.     0  10     6        0  12     6 



FIG.  666. 

Best  Steel  Frame  D  Eye  Preservers,  (fig.  666)  fitted  with 

best  smoke  or  blue  tinted  glasses,  both  in  front  and 

at  the  sides .     10s.  6d.     0  12     6        0  15    0 

Ordinary  Steel  Frame  D  Eye  Preservers,  fitted  with 

smoke  or  blue  tinted  glasses  and  with  gauze  side  shades 

5s.  6d.    0    6    6        076 



FIG.  671. 

£    s.    d. 

668  Best  Steel  Spectacles,"(fig.  618)  with  large  smoke  or  blue 

tinted  glasses  of  the  finest  quality        .        .        .        .076        0  10    6 

669  Ordinary  Steel        ditto        ditto    fitted  with  smoke  or 

blue  tinted  glasses          ....        2s.  6d.,  3s.    0    3    6 

670  Goggle     Spectacles,     steel    frame,    with    wire    gauze 

cups,  fitted  with  smoke  or  blue  tinted  glasses 

3s.  6d.,  5s.  6d.    066 

671  Goggles,  (fig.  671)  to  fit  the  head  by  means  of  an  elastic 

band,  fitted  with  smoke  or  blue  tinted  glasses       from     0     1 

£    8. 



6  to  0  10     6 

FIG.  683. 

FIG.  682.  FIG.  689. 

672  Best  Nickel  Plated  Steel  Folding  Eye  Glasses,  (fig.  640*) 

with  smoke  or  blue  tinted  Cup  Shape  or  spherical  glasses   0  10     6 

673  Ditto  ditto  ditto,          with    smoke    or    blue 

tinted  flat  glasses  ....  ...0760  10    6 

0  12     6 

FIG.  675. 

FIG.  678. 

FIG.  676. 

674  Steel  Folding  Eye  Glasses,  with  smoke  or  blue  tinted 

glasses 036  to  056 

675  Shooting  or  Hunting  Eye  Glasses,  steel  mounted,  with 

joints  and  screws  for  attaching  to  the  Hat  (fig.  675)    .076         0  10     6 

676  Ditto  ditto  ditto  double  (fig.  676)      .  150 

45,  CORNHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON.       221 

FIG.  687.  FIG.  686.  FIG.  685. 

678  French  Pattern  Spectacles,   (fig.  678)  with  Single  or  &  as°  '  a.      £  &B.  '  d. 

Double  sides,  Gold "        .  .  1  10    0  to  3    3    0 

679  Ditto            ditto            ditto                Best  Steel  ,  0  10    6        0  12    6 

It  is  not  generally  known  that  vrhat  are  termed  "  Pebbles,"  as  used  in  the  construction 
of  spectacle  lenses,  are  cut  from  Rock  Crystal.  For  such  no  better  substance  is  obtainable 
when  free  from  impurities,  being  much  harder  and  brighter  than  glass.  The  difficulty, 
however,  of  obtaining  "  Pure  Pebbles "  is  great,  and  not  until  much  labour  has  been 
expended  in  cutting  and  polishing  can  any  of  the  many  defects  be  discovered  which 
ultimately  cause  their  rejection.  It  is  in  consequence  of  a  large  percentage  of  loss  in  the 
production  of  "  Pebble  Lenses "  that  the  cost  is  so  much  greater  than  glass  ;  but  it  is 
only  apparent,  as  the  advantages  of  a  higher  polish,  the  non-liability  to  scratch  or  break, 
well  compensate  for  the  outlay. 

For  the  information  of  those  who  sometimes  imagine  their  Spectacles  no 
longer  serviceable,  Negretti  &  Zambra  beg  to  say  that  a  little  expense  will  often, 
for  all  practical  purposes,  make  them  equal  to  new.  The  re-working  of  a  pair  of 
pebbles  to  a  higher  power,  a  new  glass,  soldering  a  broken  frame,  or  a  new  spring 
to  an  eye  glass,  will  frequently  accomplish  this  end. 

These  repairs  are  executed  at  moderate  charges  and  returned  by  post  in  the 
shortest  possible  time  from  their  receipt  with  instructions. 

Spectacles  made  to  order  of  any  shape  or  material,  and  fitted  with  lenses  worked 
to  any  particular  form.  Pebbles  re-worked  and  altered  to  suit  the  variation  of 

Spectacles  or  Eye  Protectors,  Gilt  Plated  or  Nickeled,  to  prevent  rust,  at  a 
slight  advance  on  prices  quoted. 

Spectacles  suited  to  the  Sight  by  sending  an  old  Lens  or  piece  of  a  broken  one. 

680    "  SPECTACLES,  WHEN  TO  WEAR  AND  HOW  TO  USE  THEM  : "    addressed  to 
those  who  value  their  sight.      Published  by  NEGRETTI  AND  ZAMBRA. 

Price  (post-free),  6d. 


Each.  Each. 

681  Spectacle  Cases,  Leather,  various  forms  and  mountings 

6d.     0    1     0        050 

682  Oval   and   Bound   Reading    Glasses,   in   Horn   cases 

(fig.  682) 2s.  6d.    0    5    0        076 

683  Ditto        ditto    t    Tortoise -shell  case  (fig.  683)       .         .     1  10    0        220 

684  Ditto         ditto  in  Pearl,   with   Silver    mountings 

(fig.  682) 110        220 

685  Cylindrical  Lenses,  in  oblong  Horn,  Yulcanite,  or  Metal 

Frames  (fig.  685)     ....      15s.  6d. ;  17s.  6d.     1     1    0        150 

686  Print  Lenses,  of  various  sizes,  in  turned  Wood  Frames, 

for  viewing  large  Maps,  Engravings,  Photographs,  &c. 

(fig.  686)         .......  21s.    1  11    0        220 

687  Magnifying  Lenses,  mounted  in  German  Silver,  with 

Wood  Handles,  suited  for  examining   Photographs, 
Engravings,  &c.  (fig.  687)  2s.  6d.,  3s.,  3s.  6d.,  4s.  6d., 

5s.  6d.,  7s.  6d.,  8s.  6d.,  10s.  6d.,  12s.  6d.    0  15    0        150 

688  Ditto         ditto        with     Ivory      Handles      and       Gilt 

mountings  6s.  6d.,  8s.  6d.,  10s.  6d.,  12s.  6d.,  15s.  6d.     1     1    0        150 

689  Ditto        ditto        mounted  in  buffalo  Horn  or  Ebonite 

(fig.    689)    3s.   6d.,  4s.  6d.,  5s.  6d.,   6s.   6d.,   7s.   6d.    0  10    6        0  12    6 


Enabling  the  wearer  to  read  or  work  with  comfort  by  Gas  or  Candle-light. 

690  These  Spectacles  are  the  result  of  a  series  of  experiments,  undertaken  with  the 
view  to  the  manufacture  of  a  glass  that  should  possess  the  power  of  arresting  the 
heat  that  proceeds  from  gas-light  and  other  sources  of  artificial  illumination. 

This  desirable  end  having  been  attained  by  Messrs.  NEGEETTI  AND  ZAMBEA, 
they  are  enabled  to  supply  Spectacles,  the  glasses  of  which  possess  this  peculiarity; 
that  is  to  say,  that  the  great  heating  power  of  gas  and  other  artificial  light  is 
rendered  imperfectly  inert  as  far  as  regards  vision,  and  the  amount  of  light  that 
enters  the  eye  nearly  equal  to  that  which  would  do  so  through  ordinary  glasses ; 
by  this  means  the  unsightly  dark  glasses  are  superseded,  and  greater  comfort  is 
secured  while  reading  or  working  by  gas-light;  at  the  same  time  the  sight  is 
preserved  from  the  pernicious  effects  of  the  heat,  and  the  eyes  are  kept  as  cool  as 
when  reading  by  ordinary  daylight.  The  Thermoscopic  Spectacles  will  be  found, 
therefore,  to  recommend  themselves  to  those  whose  avocations  require  great 
application  to  the  desk,  more  especially  during  'the  winter  months,  in  the  banks 
and  public  offices  generally,  where  of  necessity  a  vast  amount  of  writing  and 
accountants'  work  has  to  be  done  by  gas-light. 
Price,  in  Best  Steel  Frames,  with  either  Convex  or  Concave  Lenses 

£0  15     0  to  1     1     0 








5,    COKNHILL,   E.G.,   AND    122,    REGENT    STRKET,    W.,    LONDON. 

k  D 


FIG.  700*. 

FIG.  696.  FIG.  691.  FIG.  695. 


Flower  Microscopes,  folding    up  into  convenient  size, 

with  neat  cases  for  the  pocket  (fig.  691) 
Gardener's  Microscope  in  case  (fig.  692) .... 
Seed  Microscopes,  with  glass  body,  in  case      .        .     2s. 
Beetle  or  Insect  Microscopes,  convenient  for  examining 

living  insects        .         '.         .         .         .  3s.  6d. 

Ditto  ditto  large  size,  best  mounted 

(fig.  695) 

Botanical  Microscopes,  with  three  powers,  mirror,  &c., 

in  pocket  case  (fig.  696) 



0  10 
0    5 

0    7 

046        076 
0  10    6        0  15    0 

FIG.  692. 

FIG.  698*. 

FIG.  698. 

FIG.  697. 

FIG.  697 


Cloth  Microscopes  or  Linen  Provers,  for  ascertaining 

the  number  of  threads  in  a  given  space  of  linen,  cloth, 

&c.,  in  round  case  (figs.  679  and  697*) 
Ditto         ditto       folding  for  Pocket  (figs.  698  and  698*) 

2s.  6d. 

Ditto        ditto  for  Coarse  Goods,  extra  large 
Watchmakers'  and  Engravers'  Magnifiers  (fig.  700)     Is. 
Pocket  Magnifiers,  in  Horn  mountings  (fig.  701)     . 

Ditto          ditto  two  lenses 

Ditto          ditto,  three  ditto  (fig.  703)        .         .         .3s. 
Ditto          ditto  one,  two,  or  three  lenses,  in  Tortoise-shell 

mountings  (fig.  704) 5s.  6d.     0  10     6        0  15     0 

Ditto  ditto          Tortoise-shell  and  Gold.  Pearl  and 

Silver   mountings    with   Single    or    Double    lenses, 

(fig-  705). 

Prices  various. 



FIG.  701. 

FIG.  705. 

FIG.  703. 

FIG  706.      FIG.  708. 

706     Stanhope     Lenses,      in     German     Silver     mountings 

(figs.  706  and  706*) 036 

Ditto  ditto      in  Tortoise-shell  ditto  0  10    6 

Each.  Each. 

£    s.    d.  £    s.    d. 

707      Ditto 

0  12    6 
ditto,      in  Silver  ditto 0  10    6        0  15    0 

FIG.  704. 

708  Stanhope  Lens,  mounted  with  shade  for  the  eye,  and 

tube  for  improving  the  definition,  magnifying  power 
180  diameters  (fig.  708) 

This  powerful  and  convenient  lens 
is  the  invention  of  Lord  Stanhope. 
The  portability,  low  price,  and  the 
facility  with  which  iti  can  be  used, 
recommend  it  strongly.  With  it  may 
be  seen  the  animalcule  in  water,  eels 
in  paste  and  vinegar,  farina  of 
flowers,  the  down  of  moths,  &c.  ;• 
and  if  a  drop  of  solution  of  salt  be 
spread  lightly  over  the  end  of  the 
lens,  and  viewed  without  delay,  the 
formation  of  crystals  will  be 
beautifully  seen. 

709  Coddington's    Spherical     Lens,     in      German    silver 

Mounting 3s.  6d.  0    5  0 

710  Ditto          ditto        in  Tortoise-shell        .        .        .         .  0  10  6 

711  Ditto          ditto        in  Silver 0  15  0 

712  Pocket     Magnifier,    with    two     plano-convex    lenses, 

diaphragm,   and    a   Stanhope   or   Coddington  lens, 

in  Tortoise-shell  mountings  (fig.  712) .          .  12s.  6d.,     0  16     6 

0  12    6 

FIG.  712. 

0  10 

0  15 

1  5 


The  most  useful  pocket  magnifier  or  microscope  introduced,  magnifying  power  10  to  80  diameters. 

45,  CORNHILL,  E.G.,  AND  122,  REGENT  STREET,  W.,  LONDON. 



FIG.  743. 

FIG.  741, 

FIG.  742. 

713  Concave  and  Convex  Mirrors,  Silvered  Glass,  in  turned 

Wood  Frames 16s.,  21s., 

714  Multiplying  Mirrors 10s.  6d. 

715  Black  Mirrors,  for  Artists 

716  Burning  Glasses,  in  Horn  mountings       .        .        .2s. 

717  Glass  Prisms,    for   showing   Decomposition  of  Light, 

of  various  sizes     .        .        .     '    .        .         2s.  6d.,  5s. 

718  Glass    Prisms,    two  in  a  neat  box  for  exhibiting  the 

Decomposition  of  Light  into  the  Prismatic  Colours 
and  their  Recomposition  into  White  Light,  &c. 

719  Prism  Compound  of  Flint,  Crown,  and  Plate  Glass 

720  Prisms  mounted  with  Ball  and  Socket  joint  adjustment 

on  Brass  foot        .         . , 

721  Hollow  Glass  Prism,  for  experiments  on  the  refraction 

of  Fluids,  and  for  Spectroscopes          .... 

722  Multiplying  Lenses,  in  frame  ....       2s.  6d. 

723  Claude    Lorraine    Glasses,  for  studying  the  effect  of 

colour  upon  Landscapes,  &c 

724  Colour  Tops,  a  simple  contrivance  for  exhibiting    the 

recomposition  of  white  light  from  colours 

725  Apparatus    for     ditto   ditto,   on    a  larger  scale,  with 

multiplying  wheel,  on  Stand  with  Circular  Prismatic 
Disc  (fig.  725) 

726  Kaleidoscopic    Colour    Top,    with     perforated    discs 

and  coloured  diagrams,  complete ;  in  box  . 

727  Concave  Lenses,  in  frame,  for  viewing  Engravings,  &e. 

Each.  Each. 

£    s.    d.  £    s.    d. 



1    1    0 

0  15    6 

1  10  0 
1  16  0 

0  10    6        160 

1  10    6 

1  16    0        220 

1  10    0 

1  1    0 
0  10    6 

2  10    0 

0  12    6        110 

0-10    6  to  2    2    0 



FIG.   725. 

FIG.  736. 

£    s.      d. 

£     s.    d. 

0  15    0       22 


1  10 

728  Graphoscopes,  see  page  228 

729  Diagonal  Print  Machines,  for  viewing  Prints,  &c.   . 

730  Cosmoramic  Frames  and  Lenses      .       .       .       . 

731  Print   or  Map   Lenses,  various  mountings   and    sizes, 

see  page  222 

732  Cylindrical  Magnifying   Lenses,  in  Yulcanite   mount- 

ings, 10s.  6d.,  12s.,  14s.,  16s,,  21s.,  25s.,  30s.,  35s.    2 

733  Cylindrical  Mirrors,  with  6  diagrams        .... 

734  Mirrors,  Conical,  with  12  diagrams  ..... 

735  Camera    Lucida,    Wollaston's    (Chambre    Claire},  for 

drawing  in  true  perspective,  in  case  (fig.  735)     . 

736  Ditto     ditto,  best  form  with  Shades,  &c.,  (fig.  736) 

737  Portable  Stand  for  ditto   . 

738  Camera  Lucida,  for  Microscope        ....    See  Micro  Section 

739  Beale's  Neutral  Tint  Camera  or  Reflector,  for  ditto.  See  also 

740  Draughtsman's    Camera    Obscura    (Chambre   Noire), 

for  sketching  (fig.  740)         .....  21s. 

741  Ditto        ditto    improved  Portable  (fig.  741)          . 

742  Cosmorama   or    Camera    Obscura,  for    Gardens,  r&c., 

fitted  up  to  order  (fig.  742) 

743  Prisms,  Piano-Convex,  in  Brass  mountings,  with  sliding 

adjustment  (  fig.  743  )  for  constructing  Garden 
Cameras  (as  fig.  742),  of  various  dimensions  and 
foci  .  .  .  38s.,  45s.  2  10  0  5  10  0 

1  10 

1  15 

2  10 



1  15    0        220 

45,    COBNHILL,    E.G.,    AND    T22,    REGENT    STREET,    W.;    LONDON". 


FIG.  760. 


FIG.  744. 

FIG.  761. 

£     s.    d. 


0  15    0 

1  10    0 

Set  of  Five  Lenses  of  various  forms  and  curves, 
(fig.  744),  with  a  small  Prism  to  illustrate  the  Science 
of  Optics,  in  a  hinged  case  ...... 

745  Model  of  the  Human  Eye,  showing  the   position  of 

various  humours  and  Lenses,  and  for  demonstrating 
the  cause  of  Presbyopia  or  Long  Sight ;  Myopia,  Short 
or  Near  Sight,  &c.,  &c.  In  Mahogany  Box 

746  Kaleidoscopes,  with  two  or  three  reflecting  planes  2s.  6d. 

Ditto  ditto,         on  Table  Stand      7s.  6d.,  10s.  6d. 

747  Chromeidoscope,  a  modification  of  the  Kaleidoscope 

748  Debuscope,  or  Table  Kaleidscope,    with  Plated  Metal 


749  Spectroscope,  for  Chemical  research.       See   Chemical 


750  Photometers,  Wheatstone's 

751  Ditto  for  Gas  Testing        .         .      See  Chemical  Section 

752  Radiometer,  Crook's          .        .        .     ditto  ditto 

753  Goniometer,  Wollaston's,  for  measuring  the  angles  of 

Crystals         ......... 

754  Anorthoscope,  with  twelve  diagrams  (fig.  725) 

755  Praxinoscope,  a  novel  and  pleasing  arrangement  of  the 

above  with  six  coloured  pictures          .         .         .  16s. 

756  Polemiscope,  by  means  of  which  any  object  may  be  seen, 

though  an  opaque  body  be  placed  before  it 

757  Phantascope,  for  exhibiting  the  illusion  effected  by  a 

concave  mirror,  projecting  figures  in  air    . 

758  Polyorama,  with  six  views,  so  constructed  that  day  and 

night  effects  are  produced  by  means  of  reflected  and 
transmitted  light 

759  Videoscope,    for     Reading,  Drawing,    Engraving,   &c., 

having  a  clamp  to  screw  the  Instrument  to  the  table, 
with  joint  and  sliding  adjustment  with  clamp  . 

760  Visuometer,  Photographic  (fig.  760),    for  enabling  the 

artist  to  judge  the  effect  of  a  landscape,  folding  for 
the  pocket  ......... 

761  Focussing  Glass,  Photographic  (fig.  761),  for  obtaining 

a  perfectly  sharp  image  on  the  focussing  Screen  of 
the  Camera   ......... 

Lenses  or  Prisms  of  all  kinds  made  to  order. 

Models  and  Diagrams  to  explain   and  demonstrate  the  Elementary 
Optics,  the  Theory  of  Vision,  the  construction  of  Refracting  and  Reflecting 
Simple,  Compound,  and  Solar  Microscopes,  &c.,  &c,  supplied  to  order. 



0  12    6 

£    s.    d. 

150        1  16    0 

£  6  0 
1  10  0 

0  10    6 

2  10    0        330 


1  15  0 


1  10  6 

0  16    0 

Laws  of 


FIG.  762. 



As  constructed  and  Patented  by  its  Inventor,  Mr.  C.  J.  ROWSELL,  and  shown  in  the 
class  "  Scientific  Inventions,"  at  the  International  Exhibition  (1871). 

So  simple  is  this  instrument,  that  little  need  be  said  as  to  the  mode  of  using. 
It  can  be  focussed  to  suit  any  sight — the  oldest  or  youngest,  the  longest  or 
shortest.  Plain  or  Coloured  Photographs,  when  viewed  through  the  Large  Lens, 
will  be  found  to  stand  out  with  the  roundness  and  reality  of  natural  objects.  It 
occupies  little  space,  cannot  get  out  of  order,  and  is  an  ornament  to  any 
drawing-room.  The  G-raphoscope  may  be  used  either  by  day  or  night. 

In  the  beautiful  Photographic  "Nature  Printing,"  there  is  much  that  the 
unassisted  eye  cannot  perceive,  but  which  appears  among  the  distincter  portions 
portrayed,  as  a  dark  or  light  mass  only.  The  Graphoscope,  by  a  simple  but 
effective  arrangement,  and  a  powerful  Lens  easily  adapted  to  any  focus,  "  brings 
out "  and  gives  a  Stereoscopic  life-like  effect  to  this,  and  to  the  whole  subject  in 
a  very  pleasing  and  beautiful  manner ;  also,  by  a  simple  combination,  it  forms  a 
perfect  Stereoscope  for  both  Opaque  and  Transparent  views.  The  Graphoscope, 
with  an  appropriate  selection  of  Coloured  or  Plain  Photographs,  forms  a  most 
elegant  Wedding  or  other  Present. 

Each.  Each. 

£    s.    d.  £    s.    d. 

762  No.  1.  Graphoscope,  Ordinary  Size,  with  Stereoscope, 

Mahogany  (figs.  762  and  762*) 2  12     6 

763  No.  2.               do.               do.                 Walnut       .        .  330 

764  No.  3.  Large  Size             do.                   do.           .       .  550 
No.  3*.  Extra  do.              do 660770 

765  No.  4.  The  Piccolo,  a  small  Instrument          .       .       .    1  10    0       1  16    0 
Negretti  and  Zambra  have  always  in  Stock  a  collection  of  Photographic  Yiews 

of  London  and  various  parts  of  the  World — Photographic  Flowers  and  views  of 
the  Crystal  Palace,  Sydenham — both  coloured  and  plain,  Statuary,  &c.,  &c. 

766  Plain  Photographic  Yiews,   2s.  6d.,  4s.  6d. ;    Coloured  Flowers   and  Yiews, 
4s.  and  5s. 

A  vase  containing  a  bouquet  of  Natural  Flowers  placed  in  the  field  of  the  large 
lens  forms  an  exceedingly  interesting  object.  When  the  Graphoscope  is  used  for 
this  purpose  it  should  have  the  easel  turned  down  flat  upon  the  base. 

Cartes  de  Visite,  Portraits,  &c.,  are  very  effective  under  the  Instrument. 


FIG.  767. 

FIG.  768. 

767  Stereoscopes,  plain  metal  or  mahogany  (fig.  767)    . 

768  Ditto        ditto        mahogany,  with  adjusting  eye-pieces  (fig.  768)      . 

769  Stereoscopes,  divided  form  (fig.  769),  papier  mache  body,  covered 

with  leather,  and  brass  adjusting  mounts,  with  glass  mirror 

£    s. 

0    5 
0  10 


770    Ditto      ditto    Walnut  or  other  woods,  with  ornamental  mountings    2 

FIG.  769.  FIG.  771. 


771  Cosmoramic  Stereoscopes,  Mahogany  or  Walnut  wood, 

with  Prismatic  Lenses  (fig.  771)          7s.  6d.,  10s.  6d.    0  15 

772  Ditto  ditto  Japanese  Mounting  (fig.  772) 

FIG.  772.  FIG.  773. 




Each.  Each. 

£     s.    d.  £    s.    d. 

773  Stereoscope,     with   extra  Lenses  for  Short  Sight,   in 

Mahogany  or  Walnut  wood  (fig.  773)  ...  220 

774  Ditto       ditto       in  Papier  Mache,  divided  form,  covered 

with  leather  and  ornamental  mounts  of  various  forms     2  10    0        330 


The  great  advantage  offered  by  the 
"  Magic  Stereoscope  "  over  all  other  descrip- 
tions of  the  instrument  is  its  power  of  en- 
larging the  slides  seen  through  it  to  such 
an  extent  as  to  render  them  perfectly  real 
in  appearance,  as  though  the  scenes 
themselves  were  actually  presented  to  view. 

Speaking  of  the  Magic  Stereoscope,  the 
writer  in  the  Art  Journal  says  : — "  This 
instrument  possesses  advantages  over  every 
modification  which  we  have  yet  examined. 
After  a  careful  examination  of  all  the 
conditions  of  the  Magic  Stereoscope,  we  are 
bound  to  state  that  it  is  by  far  the  greatest 
improvement  which  has  been  made  in  this 
most  interesting  instrument." 

The  prominent  position  the  Magic 
Stereoscope  has  now  for  more  than  twenty- 
five  years  held,  the  favourable  opinion  ex- 
pressed of  its  merits  by  its  numerous  pur- 
chasers, and  the  steady  and  increasing  de- 
mand, not  only  in  Great  Britain,  but  in  all  our 
Colonies,  in  America,  and  on  the  Continent, 
and,  moreover,  the  entire  absence  to  the 
present  time  of  any  competing  instrument 
of  higher  pretensions, — all  combine  to  estab- 
lish its  great  superiority,  and  to  confirm  the 
opinion  concerning  it  expressed  in  the 
critique  in  the  Art  Journal  quoted  above, 

Messrs.  NEGRETTI  AND  ZAMBEA  are 

the   Sole    Manufacturers  of    Mr.   COOK'S 

Patent  Magic  Stereoscope. 

FIG.  775. 

774°  Patent  Magic  Stereoscope,  in  Walnut,  with  Achromatic 
Lenses,  on  sliding  telescopic  stand  (fig.  774*),  with 
rackwork  adjustment  for  focussing  .  .  .  . 

10  10    0 

45,    COKNIIILL,    E.C.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  780. 

£    s.    d. 

775    Negretti    and    Zambra's  Patent   Magic   Stereoscope, 
in  its  most  perfect  form,  with  Extra  Sized  Lenses 
throughout,  the  intermediate  lenses,  Patent  Cylindrical, 
for  insuring  a   perfectly  flat,  colourless  field  and 
freedom  from  distortion  (as  fig.  775)  .         .          from 

£    s.    d. 

18  18      0 




Achromatic  Stereoscopes,  with  Opera  Glass  adjustment 

(fig.  776),  in  various  plain  mountings  .  .  25s.  1  15  0  2 

Ditto        ditto        ornamental  mountings        .         .        .220        3 

Achromatic  Stereoscopes,  with  Rackwork  Adjustment 
and  extra  large  Achromatic  Lenses,  high  magnifying 
power,  suited  for  Glass  Stereoscopic  views  .  .  2  10  0  3 

Ditto        ditto    mounted  on  Adjusting  Stand  .        .        .440        5 

780  The  Cabinet  Form  Stereoscope,  in  Walnut  with 
Rackwork  adjustment,  mounted  on  adjusting  stand, 
with  Brass  Slides  and  Clamps  (fig.  780)  ...  5 

50        660 



FIG.  782. 


781  Magazine  Stereoscopes,  to  hold  and 

exhibit     twenty-five     transparent 
Glass,  or  fifty  Paper  Slides. 

£440        £550 

782  Ditto         ditto         with  Achromatic 

Lenses    (fig.    782),    to  hold  fifty 

Glass  Yiews. 

£770      £880      £10  10    0 

783  Magazine  Stereoscope,  to  hold   100 

Glass     Yiews,     with     convenient 
adjustments    .        from  £12  12     0 

783*  Magazine  Stereoscope,  very  hand- 
somely Carved  and  Ornamented, 
to  hold  100  Glass  Yiews. 

£25    0    0  to  £30    0    0 

FIG.  784 

Each.  Each. 

£     s.    d.  £     s.    d. 

784    Hand  Stereoscope  (fig.  784),  for  rapidly  looking  over 

a  series  of  Stereographs 0  15     6 

784*  Folding  or  Book  Stereoscope,  with  Leather  cases  .        .    0  10    6  0  15    0 


785    Negretti  and  Zambra's  Series  of  Glass  Stereoscopic  Views, 
Price  3s.  6d.  and  5s.  each  : — 

England.  Venice. 

London  and  Environs.  Germany  and  the  Rhine. 

Scotland.  Belgium  and  Holland. 

Ireland.  Denmark. 

France.  Norway. 

Spain.  Sweden. 

Italy.  Russia. 

Rome.  Constantinople  and  Athens.     India. 

Switzerland.  America.  Pompeii. 

Egypt  and  Nubia. 

Holy  Land  and  Syria. 






45,    CORNI1ILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,    LONDON.  233 


786  Negretti  'and  Zambra's  Collection'of  Crystal  Palace  Views,  upon  Glass  and 
Paper,  comprising  all  the  most  interesting  views  of  the  building  and  various 
Courts,  Statuary,  &c. 

Glass £036  each 

Paper £010,, 


787     Paper  Stereoscopic  Views  of  the  following  places,  price  Is.  each. 

England.  Holy  Land.  France. 

London  and  Suburbs.  India.  Belgium. 

Scotland.  China.  Spain. 

Wales  Italy.  Holland. 

Ireland.  Switzerland.  Pompeii  and  Herculaneum. 

Egypt  and  Nubia.  America.  &c.,  &c. 


PICTURES.  Each.^        £Easch-d 

788  Plain  Mahogany  Boxes,  to  hold  100  Paper  Views    .       .    0  10    6  to  1    5    6 

789  Ditto  ditto        better  quality  for  Glass  Views          .220        330 

790  Elegant  Cabinet  Boxes,  to  hold  a  Stereoscope  with  a 

selection  of   Glass   and  Paper  Views,  &c.,   &c.  ;  of 

various  forms  and  mountings      .         .         .        £3  3s.     4    4     0        550 

Messrs.  Negretfci  and  Zambra  received  a  Prize  Medal,  1851. 
Honourable  Mention,  Paris,  1855.     The  Austrian  Gold  Medal 

For  Stereoscopic  Views  on  Glass. 

Two  Prize  Medals,  1862,  "For  beauty  and  excellence  of  Photographic 
Transparencies,  and  adaptation  of  Photography  to  Book  Illustration ;  "  and 
"For  many  Important  Inventions  and  Improvements,  together  with  accuracy 
and  excellence  in  Objects  Exhibited." 


This  Binocular  is  specially  designed  for  Service  in  the  Field.     Optically,  is  of 
high  power  ;  gives  a  large  field  of  view,  abundance  of  light,  and  perfect  definition. 

A  Glass,  to  be  really  useful  for  Active  Service,  should  possess  the  characteristics 
of  mechanical  strength,  optical  perfection,  and  be  handy  either  on  foot  or  in  the 
saddle ;  these  qualities  are  pre-eminently  united  in  the  New  Military  Binocular. 
For  Price,  See  Series  IV.,  No.  796,  page  236. 




FIG.  A.  &  791. 


All  Binocular  Glasses  named  in  the  present  List  are  comprised  in  Series  and 
Numbers,  ranging  from  1  to  7  ;  but  as  some  of  the  numbers  are  omitted  in  certain 
Series,  it  will  assist  in  the  selection  of  any  particular  Glass  if  reference  is  made  to 
the  following  Table,  where  the  approximate  size  of  the  Object  Lenses  is  marked 
opposite  each  Number.  These  Numbers  apply  to  any  one  of  the  Fourteen  Series. 

Glass  No.  1 

Size  of  Object  Lenses,  1£  inch. 
„         If      „ 



791    Twelve-lens   Achromatic   Binocular  Race   Glass  (fig.  A),  (having    Triple 
Combination  Eye  and  Object  Lenses)  very  powerful,  great  field  of  view. 

with  Solid  Leather  Case  and  Strap £660 

Aluminium  ditto  ditto £12  12     0 

See  also  No.  6,  Series  I. 

45,  CORNHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON. 



792  Binocular  Field  or  Race  Glasses,  12-lens  Combination.  The  eye-lenses  in 
these  Glasses  being  larger  than  those  usually  supplied,  a  much  greater  field 
of  view  is  obtained.  They  are  mounted  in  bronzed  metal,  the  bodies  covered  with 
leather,  and  are  made  in  seven  sizes,  all  equally  adapted  for  land,  sea  or  in-door 
use.  (Fig.  c.) 

Nos.  1,  2,  and  3  are  supplied  in  Soft  Leather  Cases,  and  admit  of  being  carried 
in  the  pocket,  where  larger  glasses  would  be  inconvenient. 

No.  1 £2  10    0      No.  5 £55 

,,2 330        ,,6 66 

,,3 3  15    0        ,,7 6  15 

,,4 440 

No.  6,  fitted  with  Double-Draw  Arrangement,  giving  higher  power,  (fig.  B.) 

£7    7 
No.  4,  5,  6,  and  7  are  supplied  in  Solid  Leather  Cases,  with  sling  straps. 

These  Glasses  are  also  mounted  in  ALUMINIUM  (about  half  the  weight  of 
those  in  ordinary  metal).     (Fig.  E  and  p.) 

No.  1 

„    2 




No.  4 

„    5 


10  10 
12  12 

No.  6,  fitted  with  DOUBLE-DRAW  ARRANGEMENT,  £14  14  0.     (Fig. 




793  Binocular  Glasses  for  Races  and  general  out-door  use,  fitted  with  12  lenses, 
giving  very  great  power  and  definition.     (Fig.  A.) 

They  are  mounted  in  metal,   Enamelled  black.     The  bodies   and   sunshades 
covered  with  leather. 

These  Glasses  are  made  in  3  sizes,  and  supplied  in  Solid  Leather  Cases  with 
sling  straps. 

No.  4 £440 

,,5 550 

,,6 660 

If  mounted  in  Aluminium  (either  bright  or  Enamelled  black) 

No.  4 £880 

,,5 10  10    0 

„     6    .        . 12  12    0 

794  Binocular  Glasses,  with  MOYEABLE  CENTRES  to  change  the  position  of 
the  lenses  to  adapt  them  to  suit  the  width  between  different  eyes,  from  10s.  to  15s. 
each  extra. 


795  The  "  Staff-Officer "  Binocular  Field  Glass,  12-lens  Combination.  This 
celebrated  Glass  is  made  in  No.  6  size  only. 

It  has  great  power  and  gives  very  fine  definition.  N.  &  Z.  strongly  recommend 
this  Glass  to  Officers  in  the  Army,  where  there  are  no  restrictions  as  to  size. 

The  mounting  and  sunshades  are  of  bronzed  metal,  and  the  bodies  covered 
with  Russia  Leather.  Price,  including  Solid  Leather  Case,  £7  7  0.  (Fig.  H.) 

Ditto  with  Double-Draw  arrangement,  giving  higher  power,  £8  8  0.     (Fig.  G.) 


796  The  "  New  Military  "  Binocular.— This  is  made  in  the  fifth  size  only,  to  fit  the 
Army  Regulation  Pouch.  (Fig.  i.) 

The  mountings  and  shades  are  of  bronzed  metal.  The  bodies  covered  with 
black  or  buff  leather,  with  Solid  Leather  Cases  to  match.  Price,  £550 

Ditto,  in  Bronzed  Aluminium,  £9  9  0.  An  allowance  of  7s.  6d.  is  made  if  the 
Case  is  not  required. 

Regulation  Pouches  supplied  to  order. 

45,    COSNHILL,    E.C  ,    AND     122,    EEGENT    STREET,    W.,    LONDON. 



797  Binoculars,  for  Marine,  Field  or  Theatre  use.  The  magnifying  power  and  field 
of  view  of  these  Glasses  can  be  varied  to  suit  near  or  distant  objects  by  means  of  a 
Revolving  Eye-Piece  containing  Three  Powers.  (Fig.  K.) 

The    mounting  is   metal,  japanned  black.      The  bodies   covered  with  Black 

These  Binoculars  are  all  supplied  in  Solid  Leather  Cases  and  are  made  in 
four  sizes. 
No  3 
„    4 


No.  3 
,    4 



.       . 









.    5 





Aluminium  — 

.       . 






,  10 






£12  12 
.  14  14 


798  Binoculars  intended  chiefly  for  Marine  Service.— Fitted  with  6-lens  combina- 
tion, and  strong  bronzed  metal  mounting,  No.  7  size,  £5  5  0.  (Fig.  J.) 

Ditto,  12-lens  Combination,  Government  Pattern,  No.  7  size,  £5  5  0. 
(Fig.  L.) 

Ditto,  6-lens  Combination,  No.  6  size,  £4    4    0. 

All  Glasses  in  this  Series  are  supplied  in  Solid  Leather  Cases,  with  Strap. 

The  Glasses  in  Series  I.  are  also  adapted  for  Marine  purposes. 


799   BinoculariField  Glasses.— 6-lens  Combination,  fitted  with  extra  long  adjusting 
tubes,  by  which  greater  power  is  obtained.     (Fig.  Q.) 

N.  &  Z.  recommend  this  Series  where  a  12-lens  Glass  would  be  too  costly. 
They  are  mounted  in  metal,  japanned  black,  and  the  bodies  covered  with  leather. 
Prices,  including  Solid  Leather  Cases,  with  Strap  : — 

No.  3  size 

99        **  99 

£2     2 
2  10 

No.  5  size 
.*   6 





800  Opera  Glasses,  very  highest  quality,  fitted  with  12-lens  combination,  and 
mounted  in  ALUMINIUM.  The  bodies  covered  either  with  Mother-o' -pearl  or 
Tortoiseshell.  (Figs.  M.  and  N.) 

These  Glasses  are  very  suitable  for  Wedding  or  Birthday  Presents,  and  are 

made  in  5  sizes. 
No.  1 

,    2 














10  10    0 

P  Q  R 


801    Opera  Glasses,  similar  to  those  in  Series  VIII.,  but  mounted  in  ALUMINIUM 
(either  bright  or  enamelled  black)  the  bodies  being  covered  with  Morocco  leather. 


No.  1 


£4  10 
5  10 

No.  3 
„    4 


£6  10    0 

7  10    0 

8  10    0 
An  elegant  Morocco  leather  or  Velvet  Flexible  Case  given  with  each  of  the 

above  Opera  Glasses. 


802  Negretti  &  Zambra's  best  quality  Opera  Glasses,  with  Ivory  bodies  and  Gilt 
Metal  Mountings,  fitted  with  12-lens  combination.  Suitable  for  presents  where 
aluminium  mounted  glasses  are  too  expensive.  (Fig.  o.) 

No.  1 £2  10    0 

,,2 330 

,,3 440 

Ditto  with  6-lens  combination. 
No.  1 £1  10    0 

,2  ,220 

No.  4 
„    5 

No.  3 


£2  10 

3  3 

4  4 




803     Opera  Glasses,  best  quality,  with    Mother-o'-pearl  bodies  and  Gilt    Metal 
Mountings,  fitted  with  12  Lenses. 

No.  1 £3    3    0    I   No.  3 

,.2 4    4    0   I      „  4 

Ditto  with  Dark  Pearl  Bodies  and  Mountings  Enamelled  Black. 

No.  1 £2  10    0   I   No.  3 

,2  3    3    0          „  4 


5    0 



.    6 

6    0 


d  Black. 


4    0 


5    0 


804  Negretti  &  Zambia's  new  pattern,  12-lens  Achromatic  Opera  Glasses.  (Fig.  E.) 

The  mountings  are   Bronzed  Metal  and  the  bodies  covered  with  Morocco 


N.  &  Z.  strongly  recommend  this  Series,  where  a  best  instrument  is  required 

in  plain  but  strongly  made  mountings.         No.  3  size          .  .        .         .£330 

No.  1  size          .        .        .        .£220         „  4    „           .  .        .        .    3  10    0 

,,2                                                2  10    0  I      „   5  440 


805  Negretti  &  Zambra's  6-lens  Opera  Glasses,  made  in  5  sizes,  either  of 
which  can  be  recommended  as  a  good  and  useful  glass  for  general  purposes. 
(Figs,  s  T  TJ.) 

.  1  15  0 

No.  4  size          .        .        .        .£220 
„   5  330 


806    Monocular  Field  or  Opera  Glasses,  best  quality,  mounted 

in  metal,  japanned   black,   and  body  covered    with    Morocco 
leather. ,    (Fig.  v.) 

No.  1  size  .        .        .  £0  10    6  No.  5  size  .        .        .  £1  10    0 

„  2    „    •        .        .    0  15    0  „   6    „    .        .        .    1  15    0 

„   3    „    .        .        .110  „    7    „  (Fig.  v.)     .    2    2    0 
,   4    ,                          150 

Prize  Medal,  1851.     Two  Prize  Medals,  1862, 




FIG.  810.- 

807  The  only  novelties  in  Opera  and  Field  Glasses  exhibited  at  the  International 
Exhibition  of  1862  were  two  by  Messrs.  Negretti  and  Zambra ;  viz.,  the  use  of 
Rock  Crystal  for  lenses,  and  Aluminium  for  the  mountings ;  the  extreme  hardness 
and  brilliancy  of  the  one,  and  the  wonderful  lightness  of  the  other,  render  them 
eminently  useful  in  the  construction  of  Field  Glasses,  &c. 

The  principal  use  of  Rock  Crystal  is  for  instruments  required  for  service  in 
Tropical  climates,  where  the  great  heat,  combined  with  moisture,  cause  the  ordinary 
glass  lenses  to  become  dull  and  stained.  The  Rock  Crystal  retains  its  polish,  gives 
a  very  brilliant  image,  and  is  not  so  liable  to  become  scratched  as  Glass. 

808  Rock   Crystal  12-lens  Combination  Binocular  Field  Glasses,  with 

Solid  Leather  Sling  Cases  and  strap  ....         £10  10    0 

The  difference  of  weight  between  Aluminium  and  the  usual  metal  mountings 
of  Field  Glasses,  &c.,  is  so  great  as  always  to  excite  astonishment,  certainly  one- 
third  less  ;  so  that  a  very  large  instrument  can  be  used  with  the  greatest  ease  and 
comfort.  This  extraordinary  lightness  is  very  valuable  in  hot  climates,  where  the 
slightest  exertion  becomes  distressing,  and  a  useful  instrument  is  often  thrown 
aside  on  account  of  its  weight.  Negretti  and  Zambra  are  now  manufacturing 
Aluminium  Opera  and  Field  Glasses  in  a  variety  of  sizes  and  forms,  fitted  with  the 
very  finest  lenses,  weighing  about  one-third  less  than  the  ordinary  instruments. 

809  Aluminium  Opera  Glasses.    See  Series  YIII.  and  IX. 

810  Ditto  Field  Glass,  as  fig.  810      ..       .       .  £10  10    0       12  12    0 


811  These  Binocular  Telescopes  are,  from  the  adjustments, 
suitable  to  every  sight  and  width  of  eyes.  The  Field  is  large 
and  clear,  with  an  abundance  of  Light,  while  the  Magnifying 
Power  is  great.  By  the  new  adjustment,  the  circles  of  the 
two  Fields  are  made  to  coincide  exactly,  so  that  all  strain 
is  taken  from  the  eyes  in  looking  through  them;  while  the 
breadth  of  the  Field  enables  the  observer  to  "  pick  up  " 
any  object  at  once. 

Negretti  and  Zambra  recommend  their  Binocular 
Telescopes  for  Yachting,  Deer-Stalking,  Military  Service 
or  general  Field  use. 

PRICES.    (Fig.  811.) 

FIG.  811. 

No.  1,  Binocular  with  Leather  Sling  Case 
»    2 
„    3 
«    4 


100  times 
150       „ 
200      „ 

Diameter  of    Height  when 
Object  Lens.     Closed  up. 

.     IJ-in.       .       9£-in. 




(About  half  the  Weight  of  those  in  Ordinary  Metal.) 

No.  1,  Binocular  with  Leather  Sling  Case    100  times      .     l£-in.       .      9§-in. 

„    2  „  „  „  .     150      „          .    If   „        .     10|   „ 

„    3  „  „  „  .     200       „          .     1$   „        .     11*   „ 

,4  .250  U   „  14^   „ 

£    a.   d. 


9  15     0 

11  10    0 

13  10    0 

12  15  0 

16    0  0 

18  10  0 

20    5  0 

812  Negretti  and  Zambia's  new  "Binocular"  Telescope.  By 
a  further  improvement  in  the  arrangement  and  combination  of 
Lenses  NEGRETTI  &  ZAMBRA  have  now  produced  a  Glass  of 
only  eight  inches  in  length,  possessing  all  the  advantages  of  the 
largest  Binocular  Telescopes. 

Great  Reduction  of  bulk  and  weight,  combined  with  High 
Magnifying  Power,  and  large  Field  of  Yiew  are  the  special 
points  recommending  these  New  Binocular  Telescopes. 

PRICES.     (Fig.  812) 
Mounted  in  Bronzed  Metal,  with  Leather  Sling  Case.  £12  10    0 

Mounted  in  Aluminium  „  „  „  16  10    0 

FIG.  812. 

NOTE. — Negretti  %  Zambra  also  manufacture  a  smaller  Binocular  Telescope,  No.  O,  with 
Object  Lenses  1  inch  diameter ;  "but  the  field  of  view  being  extremely  limited,  they 
recommend  in  preference  their  12-Lens  Binocular  Field  Glasses,  No.  6,  at  £6  6s.  and 
£7  Is.  Sec  Series  1  and  3,  pages  234  and  236. 





FIG.  817. 


£    s.      d. 

813  Perspective  Glasses,  with  mahogany  or  japanned  body, 

and  one,  two,  or  three  draws     .        .      Is.  6d.,  2s.  6d.    0    3     6 

814  Pocket  Telescopes,  two  or  three  draws,  with  Achromatic 

object    lens,  Mahogany  or   Leather   Covered   body 

(figs.  814) 0  10    6 

815    Ditto  ditto 

£    s.    d. 


0  12    6 
with  Sun  Shade    0  15    0       0  16    0 

FIG.  8H. 

FIG.  819. 

FIG.  814. 

816  Achromatic  Telescopes,  with  Leather  Case   and  Sling 

Strap 150        1  10    0 

817  Achromatic  Telescopes,  with  Screw  and  Jointed  Clip 

for  fixing    to   a   tree  or  at   side   of  Window,    &c. 

(fig.  817) '21s.    150        1  10    0 

Ditto              Ditto            with  Astronomical  Power,  in 
a  neat  Mahogany  Box 150 

818  Pocket    Rifle  Telescope,  Achromatic,  one  draw,  body 

covered  with  leather,  with  light  sling,  small,  portable, 
and  very  powerful,  to  show  Bullet  marks  at  300  to 
500  yards 1100  220 

819  Pocket  Achromatic  Telescope— 

3  draws  24-inch,  If -inch  Object  Lens  (fig.  819)   .  220 

820  Ditto, with  Sun  Shade  2  10    0 

821  Pocket  Achromatic  Telescope — 

3  draws  30-in.,  If -inch  Object  Lens     .  330 

45,   CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  822. 


£      s.    d. 

822  Pocket   Achromatic   Telescopes,    with    Mahogany  or 

Rosewood  body  (fig.  822)  :— 

Two,  three,  or  four  draw  Brass  Telescopes  with  Lenses 


12-inch 1  15    0 

18-inch  ditto        ditto 2  10    0 

24-inch  ditto        ditto 3  10    0 

30-inch  ditto        ditto 440        550 

36-inch  ditto    4 -draw,  Extra  Large  Object  Lens  7  It)     0 

823  Pocket  Achromatic  Telescope  —  solid  German  Silver 

Mountings,  with  Sun  Shade,  21-inch  three  draw, 

best  quality  (fig.  822) 4  10    0 

824  Ditto                                    Ditto                               30-inch  5  10    0 

825  Pancratic  Eye  Tubes  (Dr.  Kitchener's),  to  above  extra  0  12    6        110 

822  and  823  are  very  suitable  for  Rifle  Prizes,  especially  if  fitted  with  Pancratic  Eye  Tubes. 

826  Solid  Leather  Cases  and  Sling  Straps  for  any  of  above, 

from  each  extra  0  10     6 

FIG.  827. 

827    12-inch   Pocket    Military  Reconnoitring    Telescopes, 

best  quality,  six  draws,  very  portable,  brass  tubes 
Ditto        ditto        German  Silver  tubes  (fig.  827) 
18-in.        ditto         six-draw  Brass  tubes 
24-in.        ditto        seven- draw  ditto        .... 
30-in.        ditto        eight-draw  ditto        .        .        ... 

1  10 

2  2 

2  10 

3  10 

4  10 

FIG.  828. 

828  Negretti  and  Zambra's  Improved  Achromatic  Military  Reconnoitring 
or  Deer-Stalking  Telescope,  two  or  three  draws,  with  Sun  Shade,  bronzed 
tubes,  and  mounted  in  strong  leather  body  with  sling  strap,  or  in  Leather 
Case  with  Sling  (fig.  828) 

No.  1 

£1  15  0 
2  10  0 

No.  4 

6  10    0 


JVbs.  3,  4,  5,  and  6  are  fitted  with  Pancratic  Eye-pieces. 




829     Fitted  with  three  draws,  Taper  Body,  with  Sun  Shade 
and   Pancratic  Eye-Piece,  Object  Glass  2^-in.  dia- 
meter.    Supplied  in  solid  leather  case,  with  sling 
strap      .......... 

Ditto,        ditto    Bronzed  German  Silver,  with  Leather 

Case  and  Sling,  exceedingly  light  but  strong     . 
N.  &  Z.  recommend  this  pattern  as  being  one  of  the  finest  Telescopes  it  is 
possible  to  employ  for  Deer  Stalking. 

Each.  Each. 

£    s.    d.         £    s.    d. 

6  10    0 

10    0 

830  Aluminium  Telescopes,  two  or  three  draws,  very  light, 
Large  Object  Lenses.  Suitable  for  Presents,  or  for 
Ladies'  use,  fitted  in  leather  cases,  with  sling  straps  .  10  10  0 

12  12    0 


FIG.  832. 

831  Marine   or  Day  and  Night  Achromatic    Telescopes, 

yielding  a  large  field  and  full  body  of  light,  adapted 

for  Coast  Service          ....  21s.,  30s.,  40s.     2  10    0        330 

832  Day  or  Night  Achromatic  Pilot  Telescopes,  with  one, 

two,  or  three  draws  (fig.  832) 220        2100 

FIG.  833. 

833  Pilot  Telescopes,  One  draw  with  Shade  Tube  (fig.  833)      330        440 

834  Erect  Night  Telescope,  with  one  draw  and  Shade  Tube, 

Object  Lens  of  large  diameter  and  best  quality         .550        660 

835  Large  Inverting  Night  Telescopes 550 

FIG.  838. 

Navy  Telescopes,  Taper  Bodies,  covered  with  leather,  bronzed  Tubes,  and 
Sunshades,  one  draw  tube,  best  Achromatic  Object  Glasses. 






Length  when  closed. 
12  inches 
15      „ 
18      „ 
21      „ 
24      „ 
26      „ 
30      „, 

Diana,  of  O.  G. 

1^  inches 

If  „  . 
If  „  . 
1*  „  . 


£2    2 

2  10 

3  0 

3  10 

4  10 

5  5 

6  10 

7  10 

45,    CORNHILL,   E.C.,   AND   122,    REGENT   STEEET,   W.,    LONDON.  245 

837  Navy  Telescopes  as  above,  but    with  polished  German   Silver  tubes  and 

Sunshades.  £3  30,     £44  0,    £550,    £660  and  £880 

838  Deck  Telescopes,  one  draw  with  Spray  shade,  as  fig.  838. 

No.  of 


Diameter  of 
Object  Glass. 

1    inches 

Body  covered 
with  leather. 

£1  16    0 

2  10    0 

3  10    0 

or  Mahogany. 

4  10'  0 

FIG.  840. 

£    s.    d. 

£    s.    d. 

1  16    0        220 

839  Deck  Telescopes,  large  sizes  of  above  with  Hackwork  and  Sliding 

adjustment  (fig.  839)  £5  10    0    £7  10    0    8  10    0      10  10    0 

840  Midshipman's    Telescope,    18-inch  Brass  taper   body 

covered  with  leather,  and  Navy  Signals  inserted,  sling 
strap  (fig.  840) 

841  Ditto          Ditto,        Regulation  pattern,  German  Silver, 

with  Navy  Signals,  Sun  Shade,  and  sling  strap 

842  Marryat's  Code  of  Signals  fitted  to  Telescopes 

843  Navy  Code  of  Signals  to  ditto 

844  Straps  and  Slings  to  ditto 

845  Mariners'  Compass,  with  Bar  Needle  or  Floating  Card 

fitted  to  cap  of  Telescopes,  to  order  from 

3  3 
0  10 
0  10 
0  10 

0  18    0 

FIG.  839. 

846  Signal  Station  or  Target  Practice  Telescopes,  for  Telegraphic  and  Look-out 
puposes,  or  for  distinguishing  bullet  marks  on  targets  at  the  longest 
ranges  with  one  draw,  the  bodies  covered  with  leather,  and  with 
rackwork  and  sliding  adjustments  to  eye-pieces  (fig.  839). 



Size  of  Object  Glass. 

2  inches 
.        .       21',, 
.        .        2*    „ 
.        .        2|    „ 
.        .        3      „  .        . 

Tripod  Stands  for  above,  see  over. 


£4  10    0 

5  10    0 

8  10    0 

10  10    0 

12  10    0 



FIG.  848. 

FIG.  850. 

847  Portable  Tripod  Stands}  for  Telescopes,  of  Wood,  with 

Brass  Bolts  and  Nuts 

848  Ditto  ditto  with  Vertical  and    Horizontal 

adjustments  (fig.  848) 

849  Ditto          ditto  Brass  head,  with  jointed  Clip,  or  Cradle 

Telescope-holder,  mahogany  legs  (fig.  849) 

850  Improved     Alt -Azimuth     Stand     (fig.     850),     for 

Astronomical  Telescopes,  well  suited  for  Telescopes 
Nos.  853, 856,  and  857 ;  Strong  Metal  Mountings,  very 
rigid,  and  conveniently  portable  .... 

£    s.    d. 

s.    d. 

1  12    6        1  16    0 

2  10    0 

330        4  10    0 

12    0    0      15    0    0 

851    Captains'  or  Pilots'  Binocular  Night  or  Look-out  Glasses  (see  pages  234  to  237). 

FlG.  852. 

852    Negretti  &  Zambra's  Traveller's   Telescope  consists  of    a  highly-finished 
portable  Telescope,  with  Folding  Table  Stand  (fig.  852). 

45,   CORNHILL,    E.G.,   AND   122,   EEGENT   STREET,   W.,    LONDON.  247 

It  is  fitted  with  Terrestrial  or  day  eye-piece  of  high  magnifying  power  and 
brilliant  definition,  and  one  Astronomical  eye-piece  of  sufficient  power  to  exhibit 
all  the  phenomena  of  the  planets  and  divide  the  more  easily  resolved  of  the  double 

The  whole  instrument  is  compactly  arranged  in  a  mahogany  box  with  lock  and 
key,  forming  one  of  the  most  useful  and  convenient  Telescopes  for  Tourists  or 
Sea  coast  visitors. 

It  can  be  used  without  the  stand,  as  an  ordinary  pocket  Telescope. 
Price,  complete  in  case    .        .         .        .     £7    7    0,    £8    8    0,    £10  10    0 


FIG.  853. 

853    Negretti  &  Zambra's  Universal  Telescope  (fig.  853),  with  2^-inch  Object 

Glass,  brass  body,  japanned  black,  fitted  in  case    .        .  .        .£550 

Ditto,    with  3-inch  Object  Glass       .        .        .        .        .  .        .£660 

Ditto,    with  polished  brass  body  and  extra  Astro,  eye-piece  .         .£880 

N.  &  Z.,  in  view  of  the  increasing  demand  for  Astronomical  Telescopes  of 
moderate  price,  have  constructed  one  that,  while  it  accomplishes  eifectually  all 
required  in  an  elementary  study  of  the  heavenly  bodies,  is  equally  useful  as  a 
Telescope  for  Terrestrial  objects,  or  for  marking  in  Rifle  practice. 

It  will  show  Jupiter's  moons,  Saturn's  ring  and  moons,  and  resolve  some  of  the 
double  stars ;  while  for  terrestrial  objects,  it  will  define  well  at  a  distance  from 
10  to  15  miles,  and  will  show  bullet  marks  on  a  target  at  the  longest  ranges. 

For  Astronomical  purposes,  an  extra  eye-piece  can  be  had,  magnifying  80 
diameters,  price  12s.  6d.  Can  be  added  at  any  time. 

Firm  Garden  Stands  for  above,  see  page  246. 



FIG.  854. 


Negretti  &  Zambia's  Signal  Station  or  Telegraph  Look-out  Telescope, 
having  Rackwork  and  Sliding  Adjustments  to  the  eye-tube,  mounted  on  a 
strong  steady  tripod  table  stand,  with  universal  movements  and  hinged  clip 
for  holding  the  Telescope,  so  contrived  that  when  not  in  use,  the  Telescope 
can  be  quickly  removed  from  its  stand,  and  both  be  securely  packed  away 
in  the  stout  case  supplied  with  the  instrument  (fig.  854). 


30  inches 
36      „ 
40      „ 
44      „ 

Diam.  of  O.  G. 

2  inches 

These  Telescopes  have  sufficient  magnifying  and  defining  power  for  distinguishing 
bullet  or  shot  marks  on  a  target  at  the  longest  ranges.  Also  well  suited  for 
Coast-Guard  stations,  or  as  a  Sea-Side  Look-out-glass. 

855  Achromatic  Astronomical  and  Terrestrial  Telescope  (fig.  855),  bright  Brass 
Body,  Rackwork  and  Sliding  Adjustment  to  eye-piece,  mounted  on  a 
pillar  and  brass  claw  Table  Stand,  having  Horizontal  and  Vertical  motions ; 
fitted  in  polished  mahogany  case,  with  lock  and  key. 

Size  of 
Object  Glass.    Terres. 

2  inches.     1 
2*  „        .1 
2*  „        .1 

3  1 



With  Terres.  Eye-piece.  With  Astro.  Eye-piece.    Price. 

.     20  diameters  45  diameters  .  £10  10  0 

.    30         „  55         „  .    11  11  0 

.    40         „  70         „  .    14  14  0 

50  85  18  18  0 

Tripod  Out-of-Door  Stands  suited  for  above,  see  page  246. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT   STREET,    W.,    LONDON.  249 

FIG.  855. 

FIG.  856. 

856  Achromatic  Astronomical  Telescope  (Fig.  856),  on  handsome  brass  pillar  and 
claw  Table  Stand,  with  Rackwork  and  Sliding  Adjustments  to  Telescope, 
elevating  and  steadying  rod,  and  Achromatic  Finder,  fitted  in  polished 
mahogany  case,  with  lock  and  key. 

Size  of  Eye  pieces.  Power 

Object  Glass.         Terres.  Astro.     With  Terres.  Eye-piece.    With  Astro.  Eye-pieces.  Price. 

3  inch      .1  2      .      45  diameters        65  &  80  diameters      .  £25    0    0 

3i  „         .1  2      .      50         „  75  &  90  .    30    0    0 

3i  „         .      1  2      ,      60  80  &  95  35    0    0 




FIG.  857. 

Achromatic  Astronomical  Telescope  (Fig.  857),  same  as  No.  856,  but  with 
Tangent  Screw  and  Hook's  Universal  Joint  for  horizontal  adjustment,  and 
extra  Steadying  Rods  to  Telescope  ;  fitted  in  polished  mahogany  case,  with 
lock  and  key. 

With  Terres.  Eye-piece.    With  Astro.  Eye-pieces. 

.      50  diameters 
.      55 

.      60         „ 

Size  of 


Object  Glass. 

Terres.  Astro. 

3£  inch 

.      1            2 

3i    „ 

.      1            2 

3f    „ 

.      1            2 

4     „ 

.      1            2 

75  &    90  diameters 

80  &  95  „ 
85  &  105  „ 
90  &  110 


£36  0 

42  0 

48  0 

66  0 



858  Astronomical  Telescope,  on  Taper  Iron  Tripod  Stand,  object  glass  3  inches 

diameter,  3-ft.  9-in.  focal  length,  one  Terrestrial  eye-piece  magnifying  20 
diameters,  and  two  Astronomical  eye-pieces,  magnifying  60  and  125 
diameters,  vertical  rack  motion  and  Achromatic  finder,  fitted  in  stout  case, 
with  lock  and  key £25  0  0 

859  Ditto     ditto,  on  improved  Tripod  Stand,  with  object  glass  3£-in.  diameter, 

4-ft.  9-in.  focal  length,  one  Terrestrial  eye-piece,  magnifying  25  diameters, 
and  three  Astronomical  eye-pieces  magnifying  80,  155  and  230  diameters. 
Fig.  859 £45  0  0 

860  Ditto    ditto,    but  with  object  glass  4^-in  diameter,  5 -ft.   3-in.  focal  length, 

one  Terrestrial  eye -piece,  magnifying  30  diameters,  and  three  Astronomical 
eye-pieces  magnifying  85,  170  and  255  diameters  .  .  .  £60  0  0 

861  Telescope  Stand,  similar  to  Fig.  861,  for  large  instruments,  complete,  with 

Vertical  rack,  Steadying  rod  and  Horizontal  tangent  rack         .     £15  15     0 

45,    COKNHILL,    E.G.,   AXD    122,    BEGENT    STREET,    W.,    LONDON.  251 

FIG.  861. 

861    Negretti  and  Zambra's  Educational  Astronomical  Telescope,  No,  861,  with 
Vertical  and  Horizontal  screw  adj  ustments,  Steadying  Rod,  &c. 



FIG.  862. 


£        s. 

150     0 


862  Negretti  &  Zambia's  Universal  Equatorial  Telescope  (fig.  862), 

with  Object  Glass  4-in.  diameter,  4-f t.  9in.  focal  length,  and  four 
eye-pieces,  magnifying  80,  155,  230,  and  310  diameters 

863  Ditto,      ditto,     but  with  Object   Glass  4|  in.  diameter.  5  ft.  3  in. 

focal  length,  and  four  eye-pieces,  magnifying  8*5,  170,  255,  and 
350  diameters,  mounted  on  bronzed  iron  pillar  5  ft.  6  in.  high  .  200 

864  Ditto,     ditto,    with  Object  Glass  5  in.  diameter,  6  ft.  focal  length, 

and  five  eye-pieces,  magnifying  65,  190,  195,  240,  and  390 
diameters  ...........  275 

865  Ditto,      ditto,    with  Object  Glass  6  in.  diameter,  8  ft.  6  in.  focal 

length,  with  five  eye-pieces,  magnifying  90,  140,  275,  410,  and 
550  diameters ;  also  an  improved  Diagonal  Eye-Piece  for  Solar 
Observation  and  for  viewing  objects  near  the  Zenith  .  .  420 

Estimates  given  for  Larger  Instruments  on  application. 
Equatorial  Telescope  Stands From    42 

0    0 

0    0 

0    0 

0    0 

45,    COBNHILL,    B.C.,    AND    122,    REGENT   STREET,    W.,    LONDON.  253 

FIG.  867. 

£     s.     d. 

866  Transit  Instrument,  14  in.,  with  Telescope  having  1|  in-  aperture      880 
Ditto    ditto    24  in.,  on  portable  Iron  Stand,  with  engine   divided 

circle,  Spirit  Levels  and  Tangent  Screw  Adjustments         .        .  27  0  0 

867  Ditto    ditto    30  in.,  with  Telescope  having  2|  in.  aperture  (fig.  867)  50  0  0 
Ditto    ditto    with  two  Setting  Circles  and  Brass  Stand          .        .  60  0  0 

868  Ditto    ditto    36  in 70  0  0 

869  Astronomical  Clock,   dead  beat  escapement,  jewelled  pallets,  and 

Compensated  Pendulum,  with  steel  rod  and  Mercurial  Cistern, 

in  Plate  Glass  Case  for  hanging  on  wall 42     0    0 

870  Mean  and    Sidereal  Time   Clock,   showing  both  times   on   the 

same  dial  with  dead  beat  escapement  and  jewelled  pallets,  with 
compensated  pendulum  and  small  bell  to  strike  the  minutes,  in 
case,  with  Plate  Glass  top,  sides  and  front  .  .  .  .  .  88  0  0 

871  Small  Equatorial  Star  Finder,  for  the  use  of  Students,  4-in  divided 

circles,  achromatic  Telescope,  with  1^  in.  object  glass         .        .     12  12    0 

"With  this  instrument  any  Star  or  Planet  can  be  found  with  facilty,  and  many 
important  facts  in  astronomical  science  demonstrated. 


FIG.  868. 

FIG.  869. 

FIG.  870. 


Portable  Transit  Instrument  for  the  Determination  of  True  Time. 

Plain  Mounting  with  Box  (fig.  868)          ....        Price  £880 

869  Ditto      ditto    ditto,  with  vertical  divided  Circle,  with  Box  (fig.  869)  12  12    0 

870  Ditto      ditto    ditto,  with  Illuminating  Apparatus,  the  most  com- 

plete form  (fig.  870)  with  Box 15  15    0 

Pull  instructions  for  setting  up  and  using  the  above  Transit  Instruments  will 
be  found  in  A  Treatise  on  the  Transit  Instrument,  by  Latimer  Clark,  M.I.C.E.,  &c., 
price  5s. 

871  Object     Glasses,     best      quality,    for     Astronomical     Telescopes, 

mounted  in  brass  cells. 

1  inch  clear  aperture 


.      150 

.  220 
.  4  15  0 
.  700 
.  9  10  0 
.  14  0  0 
.  22  0  0 
.  42  10  0 
.  75  0  0 
.  125  0  0 
.  200  0  0 
.  300  0  0 
.  400  0  0 

Quotations  for  larger  sizes  may  be  had  on  application. 


£     s     d 

871°  Telescope  Eye-Pieces,  Huyghenian        ....      16s.  to  1    5    0 

872  „                    „            Dawe's  Solar 800 

873  „                   „            Transit 300 

874  „  „            Terrestrial           .        .         .         ...  1  15     0 

875  „                    „            Comet 1  10    0 

876  „                    „            Diagonal 4  10    0 

877  Sunshade  and  Brass  Cap  fitted  to  eye-piece 060 

878  Micrometer,  Double  Image,  with  Eye  Pieces,  &c.,  in  Box        .        .  20    0    0 

879  Micrometer,  with  Position  Circle,  &c 15    0    0 

880  Reflecting  Telescopes,  for  Students'  use,  mounted  on  improved 

stand,  with  endless  screw  motion  to  follow  the  stars  with 
Equatorial  Motion,  Silvered  Glass  Speculum,  5£  in.  diameter, 
with  two  eye-pieces 25  0  0 

881  Ditto,        Ditto        on  Equatorial  stand,  with  6^  in.  speculum        .    80    0    0 
«82    Ditto,        Ditto         with  85  in.  Speculum  and  three  eye-pieces        .  110    0     0 
883    Silvered  Glass  Specula  (unmounted)  best  quality. 

5J  inch  diameter 7  10     0 

63     „  „  ..900 

8*    „  17  10    0 

10      „  „  .    38    0    0 

Prices  of  larger  sizes  may  be  had  on  application. 

884  Foucault's  Reflecting  Telescope,  for  Terrestrial  or  Astronomical  observations. 
The  improvements  of  this  telescope  are  principally  in  the  use  of  a  Glass 
Speculum  coated  upon  the  surface  with  pure  Silver.  The  eye-piece  is 
an  achromatic  microscopic  arrangement  of  lenses  mounted  on  the  side 
of  the  telescope,  the  image  being  received  from  the  large  speculum  by 
a  prism,  and  the  reflected  image  examined  by  the  Microscope  Eye-Piece, 
which  is  fitted  with  rack-work  adjustment.  With  these  arrangements,  high 
powers  can  be  used,  and  large  field  of  view,  combined  with  light,  obtained. 
Mounted  on  a  table  stand,  with  simple  adjustments  (fig.  884). 

Supplied  to  order        .        .    £20    0    0 

With  simple  instructions  for  re-silvering  the  speculum. 

Gregorian  or  Newtonian  Reflecting  Telescopes  constructed  to  order. 



FIG.  889. 


Each  Each 

£     s.     d.  £    s.     cl. 

885  Botanic  or  Dissecting  Microscope,  Simple  Lenses,  a 
variety  of  forms,  with  pillar  to  screw  into  the  top 
of  the  box  containing  the  apparatus  .  lls.  6d.,  16s.,  0  17  0  1  10  0 

FIG.   892. 

FIG.  891. 

886  Botanic  or  Dissecting  Microscope,  with  Hackwork 
adjustment  and  apparatus,  in  Mahogany  Box 
(fig.  886) 150 

1  10    0 

45,   CORNHILL,    E.G.,    AND   122,    BEGENT   STEEET,   W.,    LONDON. 


FIG.  891. 



£    s.    d. 

Compound  Microscope,  with  sliding  tube  adjustment, 
mirror,  eye-piece,  and  magnifying  power,  forceps,  and 
one  microscopic  object ;  in  a  Mahogany  hinged  box 

Compound  Microscope,  with  three  magnifying  powers 
and  two  objects  and  stage  glass  for  holding  water. 
&c.,  in  Mahogany  box  (fig.  888) 0  16  0 

Compound  Microscope,  with  three  magnifying  powers, 
a  mounted  lens  for  condensing  the  light  on  opaque 
objects;  in  Mahogany  box  (fig.  889)  .  110220 

Compound  Microscope,  with  sliding  tube  adjustment, 
mirror,  four  powers,  objects,  forceps,  water  trough, 
insect  box,  stage  plates,  glass  tube,  &c.  (fig.  890) 

£    a.    d 

0  10    0 

0  18    0 



Large  Compound  Microscope,  Martin's  Improved,  best  finish,  and  lenses,  with 
Rackwork  adjustment  (fig.  891)  .....  440 

Dissecting  'or  Mounting  Microscope,  improved  form,  arranged  for  medical 
or  botanical  investigation.  The  stage  plate  is  made  of  stout  glass,  set  in 
a  circular  brass  rim  supported  on  three  legs;  beneath  the  stage  is  a 
mirror,  with  convenient  adjustment.  This  Microscope  is  fitted  with  three 
simple  powers,  ^-inch,  1-inch,  and  2-inch  focus.  Arranged  in  a  neat 
mahogany  box,  with  brass  forceps,  &c.  220 

Dissecting  Microscope,  similar  to  No  892,  but  with 
Compound  Body,  as  fig.  892,  having  Rackwork  adjust- 
ment, also  1-inch  and  ^-inch  Achromatic  Powers,  in 
Mahogany  Box,  with  brass  forceps,  &c.  ...  440 




FIG.  894,  FIG.  895*. 


Achromatic  Microscope,  with  Jointed  Pillar,  and  firm  circular  foot,  Hackwork 
adjustment  to  the  body,  sliding  clamp  for  objects  on  the  stage,  with  a  set 
of  Achromatic  lenses,  brass  forceps,  &c. ;  in  Mahogany  case  (fig,  894) 

In  three  sizes,    £1  10    0        £220        330 




Negretti  and  Zambra's  No.  1  Microscope  (suited  for  elementary  instruction 
or  amusement).  Bronzed  Stand,  rack  adjustment  to  the  body,  slide  holder 
and  diaphragm  to  the  stage,  forceps,  stand  condenser,  two  eye-pieces,  and 
two  sets  of  Achromatic  Powers,  in  Mahogany  cabinet  .  .  £3  10  0 

Negretti  and  Zambra's  No.  2  Microscope,  similar  to  No.   1,  with  Fine 
Adjustment  to  the  body,  and  1-inch  and|-inch  Achromatic  Powers 

(fig.  895*)      £4  10    0 

Negretti  and  Zambra's  No.  3  Microscope,  similar  to  No.  2,  and  fitted  with 
Polarising  Apparatus £6  10  0 

897  Negretti   and  Zambra's  No.  1A   College   Microscope,  with  Brass   stand, 

rackwork  adjustment  to  the  body,  sliding  object  stage  and  holder, 
diaphragm  plate,  Achromatic  object  lens,  dividing  to  ^-inch  and  ^-inch, 
in  brass  box,  Live  Box,  brass  forceps,  &c. ;  in  Mahogany  cabinet  with 
lock  and  key  and  drawer (Fig.  No.  1A),  £3  10  0 

898  Ditto    Ditto      Ditto,  with  Stand  Condenser,  Stage,  Forceps        .£440 

45,    CORNHILL,    E.G.,   AND    122,    EEGENT    STEEET,   W.,    LONDON. 


No.  1  A 

No.  2  B 

899  Negretti  and  Zambra's  No.  2B  College  Microscope,  as  898,  but  with  fine 

adjustment  and  lengthening  tube  to  the  body,  separate  object  lenses,  1-inch 
and  £-inch,  in  brass  boxes  ;  in  Mahogany  Cabinet          .         .        £500 

900  Negretti  ]  and   Zambra's  No.  30    College    Microscope,   with    Mechanical 

Stage,  giving  adjustment  in   two   directions,   as  No.  2  B,  in  Mahogany 
Cabinet  with  Lock  and  Key £&  10    0 

901  Negretti  and  Zambra's  No.  4D  College  Achromatic 
Microscope,  similar  to  No.  3  C,  but  with  Polarising 
Apparatus  ......... 

10  10    0 

902  Negretti  and  Zambra's  College  Achromatic  Microscope,  No.  5.  Brass  stand, 
with  Mechanical  Stage,  Rackwork  Adjustment  and  Lengthening  Tube, 
to  the  body,  Fine  adjustment  for  the  Object  lens,  rotating  object 
holder,  and  diaphragm  to  the  stage,  two  eye-pieces,  three  Achromatic 
Powers,  1  inch,  ^-inch,  and  ^-inch,  Polarising  Apparatus  with  Selenite 
Spotted  Lens,  Stand,  Condensing  Lens,  Animalculse  Cage,  Stage  Con- 
denser and  Forceps,  Curved  Forceps,  Dipping  Tubes,  Stage  Glasses, 
&c.,  &c. ;  in  Mahogany  Cabinet £18  18  0 

902°  Negretti  and  Zambra's  Student's  Binocular  Microscope,  with  convenient 
adjustment  for  width  of  eyes,  Plain  Stage,  two  Eye -Pieces,  and  1-inch 
and  |-inch  Achromatic  Object  Lenses,  Stand  Condenser,  Live  Box, 
brass  forceps,  &c. ;  in  Mahogany  cabinet  .  .  .  .  .£880 



NO.  3  C.  N0.4D. 

903  Student's  Binocular  Microscope,  as  902*,  with  Rackwork  Adjustment  to 

eye-pieces,  and  an  extra  pair  of  eye-pieces  (fig  4D.)   .        .        .  £10  10    0 

904  Negretti  and  Zambra's  Student's  Binocular  Microscope,  as  No.  903,  but  with 

extra  i-inch  Power £12  12    0 

FIG.  905. 

905  The  Naturalist's  Portable  Field  Microscope,  mounted  on  Folding  Brass 

Tripod,  with  1-inch  Achromatic  Object  Lens,  complete  with  Forceps,  &c., 
in  Mahogany  Box  (fig.  905) £3  10    0 

906  Ditto  ditto  having    1-inch    and    i-inch 
Achromatic  Lenses,  Live  Box,  Forceps,  Fishing  Tubes,  Stage  Glasses, 
Stand  Condenser,  &c.,  &c.,  in  Mahogany  Box,  very  compact,  invaluable,  to 
Mineralogists,  Botanists,  Geologists,  Entomologists  or  Travellers  £4  10    0 

45,   COBNUILL,    B.C.,   AND    122,   EEGENT   STEEET,   W.,    LONDON. 


FIG.  907. 

907  Brewer's  Microscope,  specially  constructed  for  the  Examination  and  Selection 

of  Hops,  Yeast,  Malt,  Sugar  and  Water  previous  to  use  for  Brewing. 
Fitted  with  one  Eye-piece,  1-inch  and  £-inch  Achromatic  Powers,  Con- 
denser, &c.,  &c.,  in  Cabinet  complete  as  fig.  907  .  .  .  £880 

908  Ditto        ditto,          one  Extra  Eye-piece  and  £  Objective  giving  increased 

Magnifying  Power  from  425  to  525  Diameters  ^with  perf ect  Definition  and 
Penetration,  Extra  Apparatus  in  Cabinet  ....  £15  15  0 

The  Microscopes  Nos.  895  to  908  have  been  constructed  to  supply  instruments  of 
moderate  price,  but  with  good  workmanship,  and  solid  mechanical 

Larger  and  more  perfect  forms  of  Microscope  are  described  in  the  following  pages. 

Instruments  and  Apparatus  for  Brewers'  use  will  be  found  described  with 
prices  in  Sections,  Thermometers,  page  153;  Hygrometers,  page  68;  Hydrometers  and 
Saccharometers,  Glass  and  Metal,  with  Excise  and  Government  scales,  page 
176 ;  Polarising  Saccharometers,  page  278 ;  Distilling  Apparatus,  page  193 ; 
also  an  extended  list  of  Chemical  Apparatus  at  the  end  of  this  Catalogue. 



NO.  911. 

909  Student's  Microscope  on  Brass  Stand,  with  one  Eye-piece,  one  Object  Glass 

giving    two   powers,  Live   Box  and  Brass  forceps,  packed  in  Mahogany 
Cabinet .£550 

910  Student's  Microscope,  similar  to  No.  909,  but  with  two  Eye-pieces,  two  Object 

Glasses,  Condensing  Lens  on  Stand,  &c. £770 

911  Student's  Microscope,  similar  to  No.  910,  but  with  Fine  Adjustment  to  the 

Body,  2-inch,  1-inch,  and  i-inch  Object  Glasses,  fig.  911       .         .  £8  15     0 

912  Larger  size  Student's  Microscope,  similar  to  No.  911,  but  finished  in  the  best 

possible  manner £13  13     0 

913  Student's  Microscope,  similar  to  No.  912,  but  fitted  with  Polarising  Apparatus, 

Spot  Lens,  &c £16  16    0 

45,    COENHILL,    B.C.,    AND    122,    BEGENT    STREET,    W.,    LONDON.  263 

NO.  914. 

914    Negretti  and  Zambia's  Student's  Best  Full-sized  Monocular  Microscope. 

Brass  stand,  with  Mechanical  Stage,  Hackwork  adjustment  and  Lengthening 
Tube  to  the  body,  Fine  adjustment  for  the  Object  Lens,  sliding  and 
rotating  Object  Holder,  and  Diaphragm  to  the  stage,  two  eye-pieces,  A  and 
B,  three  Best  Achromatic  Object  Lenses,  1-inch,  ^-inch,  and  £-inch,  Polar- 
ising Apparatus,  with  Selenite  Plate,  Spot  Lens,  Camera  Lucida, 
large  Condensing  Lens  on  Stand,  two  Live  Boxes  or  Animalculae  Cages, 
Stage  Condenser  and  Stage  Forceps,  plain  and  curved  Brass  Forceps, 
Dipping  Tubes,  Stage  G-lasses,  &c.,  &c. ;  in  Solid  polished  Mahogany 
Cabinet,  with  lock  and  key,  fig.  914 £25  0  0 



915  Student's  Binocular  Microscope,  fitted  with  adjustment  for  width  of  eyes,  a 

pair  of  Eye-pieces,  2-inch  and  1-inch  Object  Glasses,  Condensing  Lens  on 
Stand,  Live  Box,  Forceps,  &c.,  packed  in  Mahogany  Case     .        £12  12    0 

916  Binocular  Microscope,  similar  to  No.  915,  but  finished  in  superior  manner,  and 

with  1-inch,  1-inch  and  |-inch  Object  Glasses  (fig.  916)        .       £18  18    0 

917  Binocular,  similar  to  No.  916,  but  fitted  with  Polarising  Apparatus,  two  pairs 

of  Eye-pieces,  Spot  Lens  and  Selenite  Plate,  &c.  .        .        .        £22    0    0 

918  Binocular,  similar  to  No.  917,  but  with  Mechanical  Stage,  Fine  Adjustment, 

&c £25    0    0 

920  Binocular,  similar  to  No.  918,  but  with  Larger  Stand,  Sliding  and  Rotating 
object  holder,  spring  side  clamp,  Clamping  Arc  for  fixing  at  any  angle, 
extra  large  Condensing  Lens  on  Stand,  Glass  Trough,  two  Stage  Plates 
Fishing  Tubes,  Frog  Plate,  &c.,  in  Mahogany  Cabinet  .  £42  0  0 

45,   COBNHILL,    E.G.,   AND    122,    BEGfciNT   STREET,   W.,    LONDON.  265 

No.  921. 

§21  Binocular  Microscope,  with  Mechanical  Stage,  having  rectangular  motions, 
sliding  and  rotating  object  holder,  spring  clamp  slide,  revolving 
Diaphragm,  Flat  and  Concave  Mirrors  arranged  to  give  an  oblique  pencil  of 
light,  Clamping  Arm  for  fixing  the  instrument  at  any  angle,. Coarse  and  Fine 
Adjustments,  two  A  and  two  B  Eye-pieces,  one  C  Eye-piece,  Micrometer 
Eye-piece,  four  best  achromatic  Objectives  l^-inch,  1-inch,  ^-inch,  £-inch. 
Polarising  Apparatus,  Rotating  Selenite,  Spot  Lens,  Stand  Condenser, 
Stage  Condenser,  Side  Reflector,  Camera  Lucida,  Reversible  Com- 
pressorium,  Frog  Plate,  two  Live  Cages,  two  Glass  Stage  Plates,  Stage 
Micrometer,  Stage  Forceps,  Straight  and  Curved  Hand  Forceps,  and 
Dipping  Tubes  in  Case,  complete  in  Solid  Mahogany  Cabinet  with 
Plate  Glass  door,  fig.  921 £65  10  0 




Negretti  and  Zambra's  Large  Binocular  Microscope,  with  Mechanical 
Stage,  having  motion  in  rectangular  directions,  Sliding  and  Rotating 
Object  holder,  Spring  Slide  Clamps,  Sub-stage  with  rectangular  motions, 
revolving  diaphragm,  flat  and  concave  Mirrors,  clamping  arm  to  fix 
instrument  at  any  angle,  coarse  and  fine  adjustments,  two  A,  two  B,  one 
C,  one  D,  and  one  Micrometer  Eye-pieces,  six  Best  Achromatic  Object 
Glasses,  viz.,  3-inch,  1^-inch,  1-inch,  |-inch,  £-inch,  and  £-inch.  Polarising 
Apparatus,  Barker's  revolving  Selenite  Stage,  Paraboloid,  Spot  Lens, 
Stand  and  Stage  Condenser,  Side  reflector,  Brook's  double  Nose-Piece, 
Camera  Lucida,  Reversible  Compressorium,  Frog  Plate,  large  and  small 
Live  Boxes,  two  Stage  Plates,  Stage  Micrometer,  Stage  Forceps,  straight 
and  curved  Forceps,  Dipping  Tubes  in  case,  fitted  in  Solid  Mahogany 
Cabinet  with  Plate  Glass  door  (fig.  922) £90  0  0 


023  Negretti  and  Zambra  Large  Binocular  Microscope,  with  graduated 
rotating  Goniometer  stage  with  rectangular  motions,  graduated  rotating 
Sub-stage,  flat  and  concave  Mirrors,  clamping  arm  to  fix  instrument  at 
any  angle,  coarse  and  fine  adjustments,  two  A,  two  B,  one  C,  one  D, 
one  Micrometer  and  one  Kellner's  Orthoscopic  Eye-pieces,  eight  best 
Achromatic  Object  Glasses,  viz.,  3-inch,  2-inch,  l|-inch,  1-inch,  ^-inch, 
£-inch,  £-inch,  ^-inch,  three  Lieberkuhns,  Gillett's  Achromatic  Condenser, 
large  Paraboloid,  large  Spot  Lens,  Stand  and  Stage  Condensers,  side 
Illuminator,  Polarising  Apparatus,  Barker's  Revolving  Selenite  Stage, 
Brook's  double  Nose-piece,  Lister's  Dark  Wells,  Reversible  Compressorium, 
High  Power  Compressorium,  large  and  small  Live  Boxes,  Camera  Lucida, 
Stage  Forceps,  Stage  Micrometer,  straight  and  curved  Forceps,  two  Glass 
Troughs,  two  Stage  Plates,  two  Dissecting  Plates,  Frog  Plate,  three 
Modifiers,  Dipping  Tubes  in  case.  Fitted  in  Solid  Mahogany  Cabinet  for 
the  instrument  and  flat  Case  for  the  apparatus,  with  draw  for  containing 
Mounted  Objects,  Form  of  Stand,  &c.,  as  fig.  922  .  .  .  £150  0  0 

924  Extra  Large  Binocular  Microscope,  with  Goniometer  Stage,  Diaphragm  and 
seven  Eye-pieces,  2  A,  2  B,  2  C,  two  0  Orthoscopic  Eye-pieces,  one  D, 
one  E  Achromatic  Eye-piece,  one  Centreing  Eye-piece,  best  4-inch,  3-inch, 
2-inch,  l^-inch,  1-inch,  |-inch,  ^-incb,  ^-inch,  -g-inch,  -j^inch  Achromatic 
Objectives,  2-inch,  1^-inch,  1-inch,  ^-inch  Lieberkuhns  in  box,  Silver 
Side  Reflector,  Reversible  Compressorium,  Best  Compressorium,  Spring 
Compressorium,  Spring  Compressorium  for  high  powers,  large,  second  size, 
and  small  Live  Boxes,  Frog  Plate,  Brook's  Double  Nose-piece,  Best  Screw 
Micrometer,  Field's  Ratio  Polariscope  with  Rotating  Body  Prism,  Large 
Spot  Lens,  Large  Paraboloid,  Read's  Hemispherical  Condenser,  Gillett's 
Achromatic  Condenser,  Lister's  Dark  Wells  and  fittings,  Amici's  Prism, 
Micro.  Spectroscope,  Stage  Condenser,  Stage  Forceps,  two  pair  Brass 
Forceps,  one  Curved  Bottle  Forceps,  Stage  Micrometer  in  brass  mount 
in  morocco  case,  Maltwood's  Finder  in  case,  two  Glass  Troughs,  one  Glass 
Polyp's  Trough,  thin  front,  three  Dissecting  Plates,  two  Stage  Plates,  six 
Tubes  in  case,  box  of  :Thin  Covering  Glasses,  three  Modifiers  in  box,  Large 
Stand  Condenser  with  Double  Rod,  Camera  Lucida  with  Dark  Shades, 
Large  Flat  Walnut  Case  for  Apparatus,  with  chased  work,  and  Mahogany 
Cabinet,  with  glazed  door,  for  Microscope,  and  flat  Case  for  the  apparatus. 

£200    0    0 

No.  924  can  be  supplied  to  special  order  in  a  Solid  Spanish  Mahogany- 
winged  Case,  with  Plate  Glass  doors;  the  wings  having  a  series  of  Drawers, 
having  Porcelain  Tablets  and  numbered  Knobs,  for  holding  1,000  Microscopic 
Objects  lying  flat.  Price  Extra £22  0  0 

The  Microscopes  Nos.  922,  923,  and  924,  are  especially  suited  for 
Presentation  Instruments. 







Magnifying  Power  with  the 
various  Eye  Pieces. 

£    8.    d. 







4  in. 

9  degs. 







1  10    0 

3    „ 

13     „ 







2  10    0 

2    „ 








2  10     0 









2  10    0 

1    n 








2  10    0 

4    „ 








4  10    0 

I  „ 









i  „ 








4  10    0 










To  »» 








15  15    0 









18  18    0 




27    0    0 

Ts  » 



56  10    0 

s  > 




Immersion  arrangement  to  £th  or  £th  powers,  42s.  extra. 

th,  ^th,  and  ^th,  are  all  of  the  very  highest  class  of  Optical 





Magnifying  Power  with  the 
various  Eye  Pieces. 










8.      cl. 

3  in. 

10  degs. 







1  10    0 

2  „ 

^     » 







1  10    0 

15    „ 







1  10    0 


16    „ 







1  10    0 

f  " 

55    „ 







2  10    0 

4      9) 

75    „ 







2  10     0 


8      » 

120     „ 

130     „ 







5  10    0 
6  10    0 

Those  marked  (*)  have  adjustments  for  covered  and  uncovered  objects,  and  all  the 
screws  are  cut  to  the  Standard  Gauge  of  the  London  Microscopic  Society. 

927    Sets  of  Achromatic  Object  Lenses,  for  Microscopes  of  French  or 

German  manufacture,  combined  focus,  1-inch       .        .        .        .  £1    0    C 

Ditto        ditto,  £-inch 150 

Ditto        ditto,  i-mch  1  10    0 

45,  CORNHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON.       269 

928  Field's   Differential   or  Eatio -Micro  Polariscope,  an   instrument  for   the 

mathematically-exact  application  of  Polarised  light  in  Microscopical 
research ;  price,  with  new  rotating  body  prism,  packed  in  mahogany  cabinet 

£17  10    0 

Only  adapted  for  Instruments  having  Sub-Stages. 

929  Improved  Micro  Spectroscope.    Showing  two  Spectra  in  the  field  of  view  at 

the  same  time ;  the  small  prism  by  means  of  which  the  second  spectra  is 
produced  is  made  to  remove  from  the  field  of  view  when  only  one  spectra 
is  required  :  this  instrument  is  supplied  with  two  adjustable  slits  at  right 
angles  to  each  other,  with  adjustments  for  regulating  the  width  of  slit 
required,  and  the  eye  lens  is  also  furnished  with  rack  and  pinion 
adjustment  for  focussing  the  spectra  and  lines  under  examination.  The 
stage  for  holding  Sorby's  tubes,  wedge  cells,  &c.,  for  showing  the  spectra 
bands,  are  made  to  remove  with  the  reflecting  mirror  from  the  body  of 
the  instrument  when  not  required :  this  spectroscope  with  achromatic 
lens  to  eye-piece,  complete  as  described  above,  fitted  to  any  microscope 


For  Pocket  Microscopes  and  Hand  Magnifiers  see  pages  223  and  224. 


Each.  Each. 

930  Eye  Pieces,  Huyghenian  (figs.  930  and  930*)  .       .       .  0  10    6       0  15    6 

931  Ditto        ditto        Best  A,  B,  C,  and  D,  E,  and  F          .  0  16    0        110 

932  Ditto,  Erecting,  for  Dissecting 0  15    0        100 

933  Ditto       Achromatic 1  12    0 

934  Micrometer  Eye  Pieces 140 

935  Kellner's  Orthoscopic  Eye  Pieces,  giving  larger  field      .  1  10    0 

936  Ross's  Centreing  Glass 0  15    0 

937  Indicator  to  Eye-piece 066 

938  Brook's  Double  Nose  Piece,  for  rapidly  changing  the 

Object  Lens  or  power  of  a  Microscope       ...  1  10    0 

940  Stand  Condensers,  small  (fig.  940) 0  10    6       0  16    0 

941  Ditto        ditto         with  Large  Lens  and   convenient 

adjustments  (fig.  941) 22s.  1  10    0        1  16    0 

942  Shadbolt's  Parabolic  Condensers,  in  brass  mountings    .  1  14    0        2  15    0 
942*  Amici's  Prisms  ....,.,..  2  10    6 

943  Achromatic  Condenser,  plain 250 

944  Ditto        ditto        Gillet's 700 

945  Achromatic  Eye  Pieces,  D 0  16    0 

946  Ditto  ditto        E 0  18    0 

947  Kingsley's  Illuminator 3  18    0 

948  Reade's  Hemispherical  Condenser 220 

949  Lieberkuhn,  or  Cup  Reflector         .        .        .    10s.  6d.  0  16    0       100 

950  Rectangular  Prism,  for  use  instead  of  a  mirror       .        .  1  10    0        2  10    0 

951  Rainey's  Light  Modifier 076 

952  White  Cloud  Illuminator         ......  0  12    6 



FIG.  940. 

FIG.  961, 

FIG.  941. 

953  Stage  Condenser  or  Side  Illuminator,    mounted   on 

jointed  arm 7s.  6d. 

953*  Nachet's  Prism,  for  Oblique  Illumination 

954  Side  Speculum  Reflector,  mounted  as  ditto  (fig.  954)    . 
954*  Dark  Wells  or  Stops,  three  sizes  on  jointed  holder 
954f  Micrometer  for  Stage,  divided  on  glass,  ^th  and|  TD'55th 

of  an  inch 

955  Maltwood's  Finder 

956  Polarising  Apparatus  fitted  to  Microscope     . 

957  Tourmalines,  mounted  to  fit  eye-tube,  price  according 

to  quality  and  size from 

958  Selenite,  mounted  for  Stage      .        .        . 

959  m  Ditto         ditto         in  Brass  Mount          .... 

960  Camera  Lucida,   Wollaston's,  for   drawing    magnified 

image,  mounted  to  fit  microscope        .... 

961  Ditto  ditto  with  additional  lenses  and  shades  (fig.  961)    . 

962  Beale's  Neutral  Tint  Reflector  (fig.  962) 

963  Improved  Argand  Oil  Lamp,  adapted  for  Microscopic 

purposes  (fig.  963) 

964  Paraffin  Microscopic    or  Reading  Lamps,  in  various 

mountings  (fig.  964) 

s.    d. 

0  12    6 


2  10    0 


£     s.    d. 

1  12  0 
0  12  6 

0  10  6 
3  15  0 

0  12 

0    2 
0    7 

0  10 

1  10    0 

1  10    0        1  15    0 



FIG.  965. 

FIG.  964*. 

FIG.  963. 

£    s.    d. 

964*  Microscopic  Argand  Gas  Lamp,  with  Improved  illumin- 
ating lens  and  chimney,  and^the  stand  conveniently 
arranged  for  various  purposes  connected  with  pre- 
paring and  mounting  microscopic  objects.  This 
Lamp  can  also  be  used  as  a  Reading  Lamp  or  for 
Chemical  Operations  (fig.  964*) 

Paraffin  Microscopic  Lamps,  with  Porcelain  Shade, 
vertical  adjustment  to  both  Stand  and  Shade 
(fig.  965) 

Ditto        ditto        in  Polished  Pine  Cabinet   .        . 

Bochett's  Microscopic  Lamp  (Paraffin)  Brass  Mounted, 
with  Condenser,  Reflector,  Shade,  and  universal 
adjustments ;  in  Mahogany  case  .  . 

Porcelain  Shade,  for  Microscopic  Lamp 

Lamp  Glasses,  for  do 

Forceps,  of  several  forms,  for  taking  up  small  objects, 

dissections,  &c 2s.  6d.  0  3 

Ditto       ditto       Curved  for  Phials       .       .       .       .03 

Wood  Forceps,  Page's,  for  mounting  objects 

Stage  Mineral  Holder 

Stage  Forceps,  with  jointed  arm,  very  useful  for  holding 
objects  while  under  examination  in  the  microscope 
(fig.  975) 0  10 

Dissecting  Needles,  or  Needle  holders    .        .        .        .01 

Dissecting  Scissors •    .       .03 

Ditto        ditto        Curved 

Ditto        ditto        Spring 

Dissecting  Knives      .       . 02 

£    s.    d 









0  10    6 
0  18    6 


0    1 
0    0 


0  12    6 

0  10  6 



FIG.  985.  FIG.  975. 

Each.  Each. 

£    s.    d.  £    a.    d. 

980  Valentine's  Dissecting  Knives,  for  cutting  thin  sections 

of  soft  animal  substances,  &c 0  17     6        110 

981  Three-pronged  Forceps,  of  German  Silver,  with  screw 

adjustment 0  17  6 

982  Ditto            ditto            plain  mounting     ....  0  15  0 

983  Microscopic  Dissecting  Instruments,  in  neat  case  .        .110  2  10  0 

984  A    Selection    of  all    the     Necessary   Materials    for 

Mounting  Objects,  arranged  in  a  mahogany  box        .330        440 

985  Glass  Cell,  round,  for  holding  fluids,  viewing  circulation 

in  plants,  polyps,  &c.  (fig.  985) 016 

986  Animalculae    Cage     or    Live    Box,   for    conveniently 

examining  water  containing  animalculse,  living  insects, 

&c.  (fig.  986) 5s.  6d.    0    7    6        0  10    6 

987  Animalculae  Box,   Yarley's  Pattern,  with  raised  centre 

(fig.  987) 0  12    6        0  16    0 






FIG.  987. 

0  15    0 

Compressorium,  for  similar  purposes,  where  the  object 

requires  greater  pressure 

Ditto       ditto       Best  Lever 

Frog  Plate,  for  holding  Frogs,  Fish,  &c.,  to  exhibit  the 

circulation  of  the  blood 

Glass  Rings,  Cells,  Circles,  Squares,  &c.,  of  various 

sizes  and  thicknesses,  for  mounting  injections,  &c., 

from  per  doz.    0    30 

Plate  Glass  Stage  Plates,  with  Oval  or  Bound  cells  per  doz. 
Glass  Sides,  with  ground  edges  for  mounting  objects, 

ol!  the  best  quality,  3-in.  by  1-in.  .        .        .   per  doz. 
Thin  Microscopic  Glass,  cut  in  Squares,  per  oz. 

Ditto        ditto        cut  in  Circles       .  ...060 







0  10    6        0  12    6 

45,    CORNHILL,    B.C.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  1010. 

FIG.  1014.    FIG.  1013. 

996    Coloured  Paper  Mountings  for  Slides,    from  Is.  per  dozen. 

FIG.  997. 

FIG.  998, 

£    s.    d. 

£    s.    d 

997  Collector's  Pocket  Microscope,  with  two   powers  and  forceps    for  holding 

the  object,  in  neat  hinged  case  (fig.  997)     ...  0  10    6 

998  Pocket  Microscopes  or  Magnifiers ;  for  prices,  &c.,  see  pages  223,  224  fig.  998. 

999  Animalcules   Tubes,  or  Collecting  Bottles,  fitted  with 

corks,  for  collecting  specimens     .         .        .    per  doz.  036 

1000  Ditto        ditto        in  sets  and  pocket  cases     .         .         .  0  10     6        0  15    0 

1001  Sets  of  3  Animalculse  Fishing  Tubes,  in  case        .  026 

1002  Ditto     6            ditto            ditto 050 

1003  Writing  Diamonds 0  10    6 

1004  Cutting  Ditto 16s.  110       1  10    0 

1005  Instrument  for  cutting  Circles  of  Thin  Glass               .  1  10    0       4  10    0 

1006  Turn  Tables  for  preparing  circular  Gold  Size  Cells       .  0  10    6 

1007  Section  Cutters,  for  wood,  bone,  &c 1  10    0        220 

1008  Air  Pump  for  preparing  objects  (see  also  Pneumatic 

Section) 110        1  10    0 

1009  Brass  Injecting  Syringe  for  ditto 0  10    6       1  10    0 

1010  Mounting  Apparatus  or  Compressorium,  for  preparing 

Microscopic  objects  in  Canada  Balsam,  &c.  (fig.  1010)  0  12     6 

1011  Canada  Balsam per  bottle    010 

1012  Turpentine „         010 

1013  Spirit  Lamps   (fig.  1013)  various  sizes,  see  Chemical 

Section 026        036 

1014  Metal  Support  for  Mounting 026 


Each.  Each 

£    s.      d.  £      s.    d. 

1015  Gold  Size  ...      per  bottle  010 

1016  Asphalte  Varnish .,010 

1017  Damar      ditto V .       .       .       ,,016 

1018  Glycerine  JeUy         . ,,010 

1019  Deane's  Gelatine  Medium 020 

1020  Farrant's    ditto 020 

1021  Marine  Glue 010 

1022  JEther,  Acetic  Acid,  Liquor  Potassas,  Solution  of  Chromic  Acid, 

Turpentine,  Carmine  Solution,  Logwood  Solution,  &c.,  &c., 

per  bottle,  from  010 


1023  Complete  Apparatus  for  collecting  Animalculae,  Diatoms,  Desmids,  &c.  &c., 

consisting  of  Collecting  or  Pond  Stick,  Spring  Clip  with  bottle,  Metal 
Ring  for  gauze  net,  Spoon  and  Weed  Knife  to  screw  into  collecting  stick, 
Strainer,  Drag  Hooks,  &c £220 

1024  Collecting  Bottles,  clear  white  glass,  with  welted  necks 

fitted  with  corks  and  turned  wood  tops — 

Capacity  123  ounces 

Per  doz.  3s.          3s.  6d.  4s. 

1025  Set  of  6  Collecting  Bottles,  in  japanned  tin  pocket  case  050 

1026  Pipettes 003       006 

All  other  Chemical  Tests,  Reagents,  &c.,  &c.,  required  for  Microscopic 
Mounting  supplied  to  order. 


1027  Sorby's  Micro-Spectroscope 5  10    0 

1028  Ditto  ditto  with  Rackwork  motion  to  the 

Eye-piece .  5  15    0 

1029  Ditto      Standard  Spectrum  Scale 110 

See  also  No.  929,  page  281. 


1030  A  Set  of  Twenty-four  Microscopic  Objects,  Transparent 

and  Opaque,  dry  mounted  and  named  ;  in  a  neat  box  036 

1031  An    extensive     Assortment    of    Balsam     Mounted 

Microscopic  Objects,  of  English  and  French  mounting     010        016 

These  objects  consist  of  insects,  parts  of  insects,  such  as  wings  and  wing-cases,  stings,  tongues, 
eyes,  dissections  of  the  trachea  and  bronchial  tubes,  antennae,  legs,  the  scales  of  butterflies 
and  moths,  zoophytes,  ferns,  fuel,  mosses,  madrepores,  sections  of  recent  woods,  leaves, 
petals,  and  farina  of  plants,  feathers,  hairs,  exuviae  of  spiders  and  aquatic  insects,  algae  or 
sea  weeds,  sponges,  echinus'  spines,  shells. 

45,    CORNHILL,    B.C.,    AND    122,    REGENT    STREET,   W.,    LONDON.  275 

Each.  Each. 

£     s.     d.  £     s.    d. 

1032  Test    Objects,    Balsam    Mounted — Podura,    Hair    of 

Mouse  and  Bat,  Navicula  Hippocampus,  &c.       .         .016        020 
1032*  Entomological  Preparation— Various   Insects,   Acara 
Parasites,  &c.,  mounted  in  Canada  Balsam,  showing 
the  respiratory,  digestive,  and  nervous  systems,  and 
•  their  modifications  for  terrestrial  and  aquatic  habits  Is.     016        020 

1033  Vegetable  Preparations,  showing  spiral  vessels,  ducts, 

tissues,  raphides,  cells  and  spores  in  plants ;  sections 

of  wood,  seeds,  leaves,  petals,  fungi,  &c.      .         .        .016         020 
1033*  Polarising  Objects,  consisting  of  crystalline  salts,  hoofs, 
horn,  skin,  tendon,  fish  scales,  palates  of  mollusca, 
vegetable  substances,  starches,  &c 016        020 

1034  Anatomical  Preparations,  Transparent    and    Opaque, 

muscular  fibre  tissues,  blood  discs,  pigment  cells,  &c.     020        030 

1035  Ditto        ditto        Bacteria,  Bacilli,  &c.,  prices  various 

1036  Sections  of  Fossil  Woods,  Exogenous,  cut  in  three 

directions 0  10    6 

1037  Ditto        ditto        Endogenous,  cut  in  two  directions   .  076 
1037*  Sections  of  Limestone,  Oolite' Flint,  containing  sponges, 

fish  scales,  and  fossil  infusoria 040 

1038  Sections   Longitudinal  and  Traverse,  of  recent   and 

fossil  bones,  fossil  and  recent  Teeth,  Sections  of  Flint 

containing  Xanthidium 020        030 

1039  Diatomacese  :  Recent  and  Fossil,  numerous  varieties  of 

Navicula,     Campylodiscus,    Cocconema,    Epithemia, 

Desmidiae,  &c.,  from  various  parts  of  the  World         .016        020 

1040  Cabinet     of     polished     Mahogany     for      containing 

Microscopic  Objects,  fitted  withjdrawers  and  divisions  3     3    0 

1041  Cabinet      ditto        Spanish  Mahogany,  to   hold  1,000 

objects 660 

1042  Ditto        ditto        with  Plate  Glass  doors      ...  880 

1043  Polished  Pine  Wood  Boxes,  with  trays  to  hold  three 

dozen  objects 046 

1044  Ditto    ditto    for  six  dozen     ditto 0  10     6 

1045  Ditto     ditto    for  six  dozen     ditto    with  lock  and  key  0  12     6 

1046  Mahogany  Racks  for  holding  objects,  per  foot,  Is. 

1047  Cardboard  Boxes,  with  wood  racks,  to  hold  1  dozen  Is.,  2  dozen,  2s. 

1048  Microscopic  Tables,  of  polished  Rosewood,  Walnut,  or 

Mahogany,  the  top  covered  with  leather  or  cloth       .880      10  10     0 






Philadelphia  International  Exhibition,  1876. 

T  2 




This  Instrument  demonstrates  the  supposed  conversion 
of  Light  into  Mechanical  Motion,  invented  by  Mr.  William 
Crookes,  F.B.S.,  and  first  exhibited  by  him  at  the  Soiree 
of  the  Royal  Society,  April  7th,  1875,  and  described  by 
him  in  the  Quarterly  Journal  of  Science,  for  July,  1875,  as 
follows : — 

"  The  Instrument  which  I  have  called  a  Radiometer, 
shown  in  fig.  1049,  consists  of  four  arms,  of  some  light 
material,  suspended  on  a  hard  steel  point  resting  in  a 
cup,  so  that  the  arms  are  able  to  revolve  horizontally 
upon  the  centre  pivot,  in  the  same  manner  as  the  arms  of 
Dr.  Robinson's  Anemometer  revolve.  To  the  extremity  of 
each  arm  is  fastened  a  thin  disc  of  roasted  mica  or  pith, 
white  on  one  side  and  lamp-blacked  on  the  other,  the 
black  surfaces  of  all  the  discs  facing  the  same  way.  The 
whole  is  enclosed  in  a  thin  glass  globe,  which  is  then 
exhausted  to  the  highest  attainable  point  and  hermetically 

"  The  arms  of  this  Instrument  rotate  with  more  or  less 
velocity  under  the  action  of  radiation,  the  rapidity  of 
revolution  being  directly  proportional  to  the  intensity  of 
the  incident  rays.  Placed  in  the  Sun,  or  exposed  to  the 
light  of  burning  Magnesium,  the  rapidity  is  so  great  that 
the  separate  discs  are  lost  in  a  circle  of  light.  Exposed 
FIG  1049  ^0  a  Candle  20  inches  off  another  instrument  gave  one 

revolution  in  182  seconds.   With  the  same  Candle  placed  at 

a  distance  of  10  inches  off  the  result  is  one  revolution  in  45  seconds ;  and  at  5  inches 
off  one  revolution  was  given  in  11  seconds.  Thus  it  is  seen  that  the  mechanical 
action  of  radiation  is  inversely  proportional  to  the  square  of  the  distance.  At  the 
same  distance  2  Candles  give  exactly  double,  and  3  Candles  give  three  times,  the 
velocity  given  by  1  Candle,  and  so  on  up  to  24  Candles.  A  small  Radiometer  was 
found  to  revolve  at  the  velocities  shown  in  the  following  table,  when  exposed  to 
the  radiation  of  a  standard  Candle  5  inches  off. 

Time  Required  for   One  Revolution. 

Source  of  Radiation.  Time  in  Seconds. 

1  candle,  5  inches  off.  behind  green  glass  40 

„        5        „  „  blue        „  38 

„         5        „  „  purple     „  28 

5        „  „  orange    .,  26 

„         5        „  „  yellow    „  21 

„         5        „  „  light  red,,  20 

"  The  position  of  the  light  in  the  horizontal  plane  of  the  Instrument  is  of  no 
consequence,  provided  the  distance  is  not  altered ;  thus' two  Candles,  1  foot  off,  give 
the  same  number  of  revolutions  per  second,  whether  they  are  side  by  side  or 
opposite  to  each  other.  From  this  it  follows  that  if  the  radiometer  is  brought 
into  a  uniformly  lighted  space  it  will  continue  to  revolve. 

"  In  diffused  daylight,  the  velocity  was  one  revolution  in  from  1*7  seconds  to  2'3 
seconds,  according  to  the'intensity  of  the  incident  rays.  In  full  Sunshine,  at  10  A.M., 
it  revolved  once  in  0'3  second,  and  at  2  P.M.  once  in  0'25  second. 

"  When  heat  is  cut  off  by  allowing  the  radiation  to  pass  through  a  thick  plate 
of  Alum,  the  velocity  of  rotation  is  somewhat  slower." 
1049     Crookes'  Radiometer,  with  Black  and  White  Discs  (as  fig.  1049)  on  Stand 

£0  10    6 

Ditto        ditto,         with  Double  Vanes  Rotating  in  opposite  directions,  on 
Stand .        £110 

For  further  details  of  Preliminary  Experiments  and  Researches,  &c.,  &c., 
see  Pamphlet,  Crookes'  Radiometer.  Price  Is. 

45,    COENHILL,    E.G.,    AND    122,    EEGENT   STBEET,    W.,    LONDON.  277 

|H|:    NEGRETTI  0    ZAMBRA.    '"•';i!|| 

FIG.  1053*.  FIG.  1053. 


Each.  Each 

£    s.    d.        £     s.     .1. 

1050  Tourmaline  Polariscope,  elementary  form — two  plates 

of  tourmaline  arranged  in  Spring  Wire  Forceps  for 
holding  any  crystal  to  be  examined  between  them, 
very  useful  for  testing  Pebble  Lenses  in  Spectacles  .  150 

1051  Reflecting  Polariscope,  Malus's.     The  Polarising  and 

Analysing  bundles  are  formed  of  very  thin  plates  of 
Glass  mounted  in*  brass  frames  on  a  metal  stand, 
adjustable  at  any  desired  angle.  Between  these 
Bundles  or  Mirrors  is  a  stage  for  holding  Crystals, 
&c.,  to  be  examined,  this  stage  having  horizontal 
movement,  with  a  graduated  circle  for  noting  the 
angle  of  rotation,  &c.  .......  330 

1052  Biot's  Improved  Black  Mirror  Polariscope.    In  this 

instrument  Black  Glass  Mirrors  are  used  instead  of 
the  Bundles  of  Glass,  and  these  Mirrors  are  fitted  with 
Divided  Arcs  for  adjusting  them  to  any  angle.  The 
rotating  stage  has  also  a  Divided  Circle  and  a  spring 
clip  object  holder  to  support  the  crystals,;  &c.,  under 
examination.  Complete  with  Tourmaline  Plate  of 
Selenite  of  uniform  thickness,  Double  Image  Prism, 
brass  frame  for  showing  polarising  structure  produced 
by  unequal  pressure  in  a  piece  of  annealed  glass,  with 
diaphragm  of  greyed  glass,  &c. ;  in  Cabinet  .  7  10  0 

1053  Woodward's  Table  Polariscope  (fig.  1053),  for  conve- 

niently illustrating  the  interesting  phenomena  of 
Polarised  Light ;  fitted  either  with  a  Bundle  of  thin 
glass  or  a  black  mirror.  Large  and  small  stage  with 
spring  object  holder,  E/ack-work  adjustments  to 
eye-tube,  Powers,  &c.,  &c.,  complete  in  a  Cabinet 
forming  a  Stand  for  the  instrument  ....  10  10  0 

Woodward's  Polariscope  can  be  supplied  for  use  with  the  Oxy-Hydrogen 
Microscope,  at  a  slight  additional  cost. 


FIG.  1055. 

1054  Tourmaline  Polariscope,  a  frame,  having  a  revolving  disc  carrying  a  series 

of  Crystals,  which  may  be  successively  brought  between  the  Tourmalines ; 
each  of  the  latter  can  be  made  to  revolve  in  its  own  plane,  and  thus  place 
their  axes  parallel  or  perpendicular  to  each  other  at  pleasure,  and  vary 
the  phenomena  of  each  crystal £4  10  0 

1055  Soleil's  Polariscope  or  Saccharometer,  improved  by 

Duboscq,  for  estimating  the  value  of  fluids,  &c.,  with 

the  most  recent  improvements  (fig.  1055)    ...  16     0     0 

1056  Laurent's    New   Shadow  Polarising   Saccharometer,   having   two    series 

of  divisions,  one  for  the  percentage  of  Sugar,  and  the  other  graduated 
for  general  Laboratory  Work.  Complete  with  one  Gas  Burner,  fitted 
with  two  Jets,  three  Glass  Tubes,  &c.,  &c.,  mounted  on  a  Bronzed 
Adjusting  Stand Price  hi  Box  18  0  0 

1057  Ditto,     ditto,  of  the  most  complete  form,  having  all 

recent  improvements,  Gas  Burner  with   two   Jets, 

four  Glass  Tubes,  &c.,  (fig.  1057)  Price  in  Box    30    0    0 

This  Saccharometer  is  of  much  greater  accuracy  than  previous  arrangements, 
and  is  now  adopted  by  the  French  Government.  In  ordering  the  Saccharometer 
the  approximate  pressure  of  Gas  to  be  used  should  be  stated. 

1058  Eolipyle. — If  Gas  is  not  available,  or  if  the  pressure  be  feeble  and  irregular, 

it  is  advisable  to  use  the  Eolipyle,  burning  Spirit  instead  of  Gas. 

(fig.  1058)  Price        .        .£330 

Instructions  for  use  are  sent  with  each  instrument. 

1059  Double  Image  Prism,  Selenite  Disc  of  equal  thickness,  and  Three-hole  Slider 

for  ditto,  for  showing  the  production  of  white  light  by  the  union  of  the 
complementary  colours £110 

1060  Unannealed  Glass,  various    shapes,  for  showing  the 

permanent  polarising  structure  of  glass  that  has  been 

uniformly  heated  and  suddenly  cooled        ...  056 

45,    CORNHILL,    B.C.,    AND    122,    EEGENT    STREET,    W.,    LONDON. 







Brass  Frame,  for  showing  the  transient    polarising      Each. 

structure  communicated  by  Pressure  to  a  piece  of        s> 

annealed  glass 

Apparatus,  for  showing  the  same  effect  by  the  unequal 

application  of  Heat , 

Polarising  Eye-piece  of  thin  glass,  in  brass  mounb 

Nicol's  Single  Image  Calc-Spar  Prism    .       .  12s.,  15s,    1  10    0 

Nicol's  Double  Image  Prism  of  Calc-Spar     . 

Tourmalines  of  various  sizes  and  colours       .        .  10s.    0  12    6 

Thin  Selenite  Plates  of  equal  and  unequal  thickness, 

developing  uniform  or  various  colours 

£      a.    d. 

0  10    0 

0  8 
0  5 
2  2 

0  18 

1  10 

030        040 

FIG.  1068. 

1068  Selenite  Designs  are  formed  of  pieces  of  Selenite  different  in  thickness 

arranged  in  a  variety  of  forms,  such  as  cubes  or  stars,  for  showing  the 
beautiful  colours  produced  by  the  varying  thickness  of  the  film  of  Selenite. 

each     10s.  6d.     £1  10    0 

1069  Design  in  Selenite,  with  motto  on  ribbon,  "Forget-me- 

not  »_i  (fig.  1068) 018 

1070  Thistle,  in  Selenite,  with  motto  on  coloured  ribbon, 

"  Dinna  Forget  "—3 0  18 

1071  Tulip  in  Selenite— 2       .  0  18 

1072  Selenite  Design  of  a  Gothic  Church  Window      .  44 

1073  Circular  Plate  of  Selenite,  ground  Concave,  to  develop 

the  colours  in  rings      .......  0  16 

1074  Rhombs  of  Iceland  or  Double  Refracting  Spar,  to  show 

the  multiplication  of    images  afforded  by  peculiar 

structure  of  the  crystal        .        .          5s.  6d.,  7s.  6d.    0  10    6        1  10 

1075  Plates  of  Quartz,  Arragonite,  Amethyst,  Topaz,  Calc-Spar,   Borax,   Nitre, 

Beryl,  Bochelle  Salts,  Sugar,  Bi-chromate  of  Potass,  Sulphate  of  Iron, 
cut  at  right  angles  to  their  axes,  for  exhibiting  coloured  rings,  compound 
figures,  bars  and  cross-bars,  screws,  and  crosses,  &c.  10s.  6d.  110  200 

1076  Sliders,  with  fish  fins  and  scales,  laminae  of  human  cuticle,  sections  of  teeth, 

bones,  hoofs,  horns,   and  tendon,  various  chemical   salts  and  vegetable 
productions,  &c.,  preserved  in  Canada  Balsam,  to  exhibit  their  polarising 
structure ;  adapted  for  the  Table  Polariscope     .         .016        026 
1076*  Microscopic  Quartz  Lenses,  £2  10s.  to  £6  10s.,  according  to  Diameter. 



Polarising  Apparatus  fitted  to  Table  or  Lime  Light  Microscopes. 

Polarisation  of  Light.     By  ~W.  Spottiswoode,  L.L.D.,  late  President  of  the 
.Royal  Society,  &c.    New  Edition  with  numerous  Illustrations.    Crown  8vo.   3s.  6d. 

45,    CORNHILL,    E.G.,    AND    122,    EEGENT   STREET,    W.,    LONDON.  281 


FIG.  1078. 

1077  Negretti  &  Zambia's  Pocket  Spectroscope,  in  Brass 

Mountings,  plain  Slit 

1078  Pocket  Spectroscope,  for  observing  the  Rain   Band, 

with  adjustable  slit,  will  show  many  of  Fraiinhofer's 
lines  (fig.  1078) 

1079  Direct  Vision  Rain-Band  Spectroscope,  larger  size,  of 

very  great  dispersive  power          ..... 

1080  Table  Spectrum  Apparatus  (or  Spectroscope),  simple 

form  for  Chemical  Analysis 

£   a.    d. 

£    s.    d. 

1  15    0 

2  10    0 
7  10    0 

FIG.  1081. 

1081  Spectroscope,  Duboscq's  arrangement,  one  Prism,  horizontal  Telescope,  and 

transparent  Micrometer,  Gas  Burner,  and  forceps;  on  adjusting  Stand, 
(as  fig.  1081) £16  10    0. 

1082  Table  Spectroscope,  with  one  Prism,  Eye-piece,  and 

divided  Circle 10  10  0 

1083  Ditto        ditto,        with  Two  Prisms      ....  17  10  0 

1084  Ditto        ditto,        with  Four  Prisms     ....  35    0  0 

1085  Table  Spectroscope,  with  two  Prisms,  high  and  low 

Power,   divided   Circle,   Comparison  Prism,    Micro 

Scale,  two  Eye-pieces  in  Box 14    0    0 



£    a.    d. 

0  15    0 

£    s.    d. 


1086  Prisms  of  Glass,  of  various  Density        .        .£110 

1087  Bisulphide  of  Carbon  Prisms 

1088  Spring  Stage,  for  studying  the  absorption  Spectra  of 

coloured  glasses 0  12     0 

1089  Gladstone's  Wedge,  for  exhibiting  the  absorption  spectra  1  12     0 

1090  9-inch  Glass  Tube,  with  Stop-Cock,  for  examining  the 

dark  lines  seen  in  gases  and  vapours  ....  0  12    6 

1091  A  Divided  Tube,  with  two  compartments  and  two  flasks,  connectors,  stop-cock 

&c.,  for  exhibiting  the  increase  of  dark  lines  with  increased  temperature 

and  length  of  vapour 220 

Bunsen's  Steatite  Burner,  with  Copper  Cone,  mounted 

on  a  stand  (M  fig.  1081) 0  12  6 

Spectroscope  Forceps  (or  Pincettes),  on  an  adjusting 

support  (N  fig.  1081) 0  11  0 

Bock  Salt  Prisms  and  Lenses,  Quartz  and  Iceland  Spar  Lenses  or  Prisms 




supplied  to  order. 

FIG.  1096. 

FIG.  1095. 


1095  Complete  with  Apparatus  for  producing  and  Purifying  the  Gases.     Full 
size  Gas  Bags  and  Pressure  Boards.     Flexible  Conducting  Tubes.     Brass  Connec- 
tions, &c.,  &c.    Best  Lime  Clock.    Mahogany  Portable  Tripod  Stand,  as  shown  in 
fig.  1095 ...     £34    0    0 

1096  Ditto  ditto  with  Microscope  (fig.  1096)        .        .     £42    0    0 

1097  Professor  Roscoe's  Lectures  on  Spectrum  Analysis  (Third  Edition),  largely 
Illustrated.  Six  Lectures  on  Spectrum  Analysis  and  its  Applications,  delivered 
before  the  Society  of  Apothecaries.  Price  £1  Is. 

*  See  Section  Electric  Light  for  Lantern  Spectrum  Apparatus. 



Negretti  and  Zambia's  Improved  7-inch  Azimuth  and  Altitude  Instrument, 

Or  Transit  Theodolite  (Fig.  1107).     See  page  285. 

The  construction  and  accuracy  of  the  instruments  enumerated  in  this  section 
being  of  the  first  importance,  Messrs.  NEGRETTI  AND  ZAMBBA  devote  special  atten- 
tion to  this  particular  branch  of  manufacture,  to  insure  the  most  perfect  finish  and 
precision  that  can  be  obtained  by  modern  improvements  in  machinery,  dividing 
engines,  &c. 



FIG.  1100. 


1098  3-inch  Theodolite,  divided  on  Silver,  with  Telescope  and 

tripod  stand  ......... 

1099  4-inch  Theodolite,  divided  on  Silver,  with  three  tangent 

screws,  tripod  staff,  &c.,  complete        .... 

1100  5-inch  Best  Theodolite,  divided  on  Silver,  reading  to  1 

minute,  with  three  tangent  screws,  rack  work  adjust- 
ment to  telescope,  tripod  staff,  complete ;  with  stout 
mahogany  box,  improved  screwed  packings,  strong 
brass  handle  and  loops  adapted  for  a  strap  (fig.  1100) 

1101  6-inch   Best  Theodolite,   divided  on  Silver,  reading 

to  20  seconds        ........ 

1102  7-inch  ditto  ditto          to  10  seconds 

1102*  3-inch  Transit  Theodolite  with  Tripod  Staff 

1103  4-inch  ditto          ditto     reading  to  1  minute 

1103*  5 -inch  ditto  ditto  best,  divided  on  Silver,  reading  to  1 
minute,  with  Diagonal  Eye  Piece  (fig.  1103*).  The  tangent  and 
clamping  adjustments  are  of  the  most  approved  construction  . 

1104  5-inch  ditto         ditto  divided    on    Silver,  reading 

to  1  minute,  complete  with  Illuminated  Axis,  Lamp,  and  other 
Astronomical  Appendages    ....  ... 

s.    d. 

18  18  0 

21     0  0 

24    0  0 

31  10  0 

35  10  0 



29    0    0 

0    0 

45,    CORNHILL,    E.C.,    A.ND    122,    REGENT    STREET,    W.,    LONDON.  285 

FIG.  1103*.  FIG.  1114. 

£     s.     d. 

1105  Transit  Theodolite,  6-inch,  best,   divided  on  Silver,  reading  to 

20  seconds 36     0 

1106  Ditto  r  ditto,  6-inch,   reading  'to    10    seconds,    with 

Astronomical  Appendages      .......  41     0    0 

1 107  Ditto  ditto,  7-inch  or  Alt-Azimuth  and  Altitude  Instrument    The  vertical  and 
horizontal  circles  are  divided  on  Silver,  reading  to  10  seconds,  improved  magnify- 
ing readers   to  the  divided  circles,   inverting  erecting   and  diagonal  eye-pieces, 
tangent  screw  adjustment  levels,  locking'plates,  with  tripod  stand  and  Mahogany 
Cabinet  for  the  instrument,  with  lock  and  key  (fig.  1107)  .         .         .         .     48  10    0 

1108  Alt-Azimuth  and  Altitude  Instrument,  8-inch  Illuminated  Axis, 

with  Lamp,  &c.,  complete  as  above 56    0    0 

1109  Ditto  ditto  10-inch,  with  ditto 90    0    0 

1110  Ditto  ditto  10-inch  with  Micrometer  to  Declination 

Circle 95    0    0 

1111  Ditto     ditto,     12 -inch,  with  Ditto 110    0    0 

1112  Ditto     ditto,     12  inch,  with  Micrometer  to  Declination  Circle      .120    0     0 

1113  Transit  Theodolite,  5-inch,  as  specially  made  for  the  War  Office, 
with  Solid  Vertical  Circle  and  covered  Arcs,  having  three  horizontal  and 
two  Yertical  Yerniers,  fitted  on  Locking  Plate  in  stout  Mahogany  Box, 

and  with  firm  Tripod  Stand 30    0    0 

1114  Everest's  Theodolites,  4-inch,  divided  on  Silver  reading  to  30 

seconds,  with  triangular  locking  plate  (fig.  1114)  with  Tripod 

Stand      .         .         , 22     0  0 

1115  Ditto    ditto,    5-inch  ditto  20  seconds     .        .  .        .        .  26  10  0 

1116  Ditto     ditto,     6-inch,  reading  to  20  seconds 33    0  0 

1117  Ditto     ditto,     7-inch,  reading  to  10  seconds 37     0  0 

1118  Ditto     ditto,     10-inch,  reading  to  10  seconds,  with  open  braced 

stand,  lantern,  and  axis  level 63    0    0 

Instruments  more  finely  divided,  21s.  extra. 

Fcr  description  and  prices  of  larger  Transit  instruments,  &c.,  &c., 
see  Section  Astronomical  Instruments. 



FIG.  1120. 


1119  10-inch  best  Dumpy  or  Gravatt's  Level,  with   Achromatic  Telescope  and 

rackwork  adjustment,    divided  Silver   Ring  Compass,  mirror  and   cross 

Level,     strong  brass     parallel    plates,    with    mahogany  tripod      staff, 

.and  case ..    £13  13    0 

1120  12-inch                  ditto                 (fig.  1120) ...  14  14    0 

1121  14-inch                   ditto                     ditto     ...  16  16    0 

1122  18-inch                   ditto                     ditto     ...  18  18    0 

1123  24-inch                   ditto                     ditto     .  22    0    0 
Dumpy  or  Gravatt's  Levels,  without  Compasses : — 

1124  10-inch                   ditto                        ditto     ...  12  10    0 

1125  12-inch                  ditto                       ditto     ...  13  10    0 

1126  14-inch                    ditto                       ditto  15  10    0 

FIG.  1127. 

FIG.  1130. 



Best  Y  Level,  with  12-inch  Achromatic  Telescope  and  rackwork  adjustment, 
Compass,  tangent  screw  adjustment,  parallel  plates,  in  case,  with  tripod 

staff  (fig.  1127) £17  17    0 

Best  Y  Level,  with  18-inch  Telescope     ....  18  18    0 

Ditto  ditto,  with  24-inch  Telescope        ....  22    0    0 

45,  COENHILL,  E.G.,  AND  122,  REGEN1  STREET,  W.,  LONDON. 


1130  Negretti  and  Zambra's  Improved  Ordnance  Pattern  15-inch  Dumpy  Y 
Level,  with  reversing  and  adjusting  Y's  to  telescope,  divided  Level, 
Silver  ring  Compass,  Tangent  Screw  and  Clamp  on  limb,  parallel  plates, 
mahogany  tripod  stand  and  Box  with  strap  (fig.  1130). 

£18  18    0 
Ditto  ditto  24-inch 22    0    0 

Theodolites  and  Levels  mounted  with  improved  Locking  Plates,  as  fig.  1114, 
at  about  35s.  to  50s.  extra  charge,  according  to  the  size  of  the  instrument. 

1131    Solid  Leather  Cases  for  Theodolites,  with  Straps,  35s.  £200 


FIG. 1135. 

FIG.  1132. 

FIG.  1134. 

£     s.     d. 

£    s.    d. 

1132  Drainage  Level,  of  Brass,  with  plain  sights,  ball-and- 

socket  joint  (fig.  1132) .        .        .        ...        .        .     1  15    0        2  10    0 

1132*  Ditto  ditto        with  Tripod  Stand         :  330 

1133  Improved  Drainage  Level,  with  adjustment  to  the 

sights,  ball-and-socket  joint,  and  tripod  stand   .  440 

1133*  4-inch  Pocket  Spirit  Level,  or  Clinometer,  brass  frame,  with  sights  and 
graduated  arc  for  determining  the  inclination  of  strata,  &c.,  with  socket 
for  staff,  in  mahogany  box  (see  also  Inclinometer)  .  .  .  3  10  0 

1134  Drainage  Level,  Ordnance  Pattern,  best  mounted,  with  plain  sights,  spring 

adjustments  to  level,  in  mahogany  box  (fig.  1134)  with  tripod  stand  550 



FIG.  1136. 

1135  8-inch  Drainage  Level,  with  rackwork  adjusting  Telescope,  parallel  plates, 

in  mahogany  case  and  tripod  stand  without  Compass  (fig.  1135)  £660 

1136  8-inch  Drainage  Level,  with  rackwork  adjusting  Telescope,  with  Compass, 

Cross  Level,  parallel  plates,  in  mahogany  case  and  tripod  stand  (fig.  1136) 


1136*  Spirit  Levels,  mounted  in  polished  mahogany  frames, 

with  brass  top  (fig.  1136)  :— 

Length— inches        .         4.          5.          6.          7.          8.          9.          10.         12. 
Price  .        .       2s.  6d.    3s.     3s.  6d.    4s.     4s.  6d.    5s.      5s.  6d.      6s. 

1137  Ditto  ditto  Brass-tipped  at  bottom.    Superior  finish. 

Length— inches      ...  6.  8.  10.  12. 

Price  ....  4s.  6d.       5s.  6d.        6s.  6d.          7s.  6d. 

1138  Ditto  ditto  Brass-plated  at  Bottom     5s.  6d.       6s.  6d.        8s.  6d.        10s.  6d. 

FIG.  1136. 

FIG.  1141. 

FIG.  1140. 

1139  Spirit   Levels,  rosewood  frames,  and   German   silver 

mountings  : — 

Length— inches        ...         6.  8.  10.  12.  18. 

Price  .        .        .        .6s.  6d.     7s.  6d.     10s.  6d.     12s.  6d.     16s.  6d. 

1140  Spirit  Levels,  plain  Brass  mountings  (fig.  1140)  : — 

Length— inches  4.          5.  6.          8.         10.          12. 

Price  ....  2s.      2s.  6d.  3s.  6d.     5s.       7s.  6d.      10s 

1141  Spirit  Levels,  Brass  mountings,  with  adjusting  screws 

and  best  ground  tubes  (fig.  1141) : — 

Length— inches    3.        4.        5.        6.        7.        8.        9.        10.        11.        12. 
Price      .        .    6s.     8s.      10s.    12s.    14s.    16s.    18s.     20s.      22s.      24s. 

'If  with  divided  tubes,  extra. 

45,   CORNHILL,    B.C.,   AND    122,    REGENT   STREET,    W.,    LONDON.  289 

FIG.  1142. 



1142  This  important  Surveying  Instrument,  as  shown  fig.  1142,  measures  distances 
and  altitudes  with  accuracy  and  great  economy  of  time,  it  accomplishes  the  work 
of  Theodolite,  Level  and  Chain,  and  can  be  used  as  a  Transit  Theodolite. 

Eckhold's  Patent  Omnimeter,  5-inch,  reading  to  one  minute  .        .  £45  0  0 

Ditto                ditto        6-inch,  reading  to  20  seconds      .        .        .    50  0  0 

1143  Taochiometer,  5-inch,  complete  in  Stout  Mahogany  Box       .        .    36  0  0 
Ditto        ditto    6-inch 40  0  0 

Printed  instructions  for  use  supplied  with  each  instrument. 

Each.  Each. 

£    s.    d.  £    s.    d. 

1144  Spirit  Level  Tubes,  plain,  marked  and  warranted,  per  inch  003 

1145  Ditto        ditto        ditto  best  ground      .  006 

1146  Ditto        ditto        ditto  best  ground  and  graduated  „  006 

1147  American  Universal  Hand  Level,  for  levelling  floors, 

ceilings,  or  walls 0  16    0 

1148  Circular  Pocket  Spirit  Level  (fig.  1148)  ....  066 


1149  Under-ground  Theodolite  for  Mining,  Surveying,  Levelling,  or  Military  Service 
(fig  1149).  Combining  in  one  instrument,  the  conveniences  of  a  Y  or  Dumpy  Level, 
Circumferenter,  and  a  Theodolite.  On  the  top  of  the  vertical  axis  of  the  instrument 
is  a  Compass  with  divided  ring  reading  by  verniers.  On  two  sides  of  this 
compass  are  Spirit  Levels  with  the  usual  adjustments  for  Azimuth  observations. 
Attached  to  the  limb  of  the  instrument  is  a  vertical  divided  circle,  upon  which  is  a 
Telescope  with  Rackwork  adjustment  mounted  in  reversing  and  adjusting  Ts.  A 
Spirit  Level  is  placed  upon  the  Telescope  similar  to  a  Theodolite.  Vertical  angles 
are  obtained  and  read  off  on  the  vertical  divided  circle  by  two  arms  and  a  vernier 
scale  attached  to  the  axis  of  the  Telescope. 

The  Telescope  has  cross  wires  in  the  Eye  Tube.  Clamps  and  tangent  screws 
are  attached  to  the  horizontal  and  vertical  movements.  Tripod  Stand  and  mahogany 
box  for  the  instrument Price  .  £22  0  0 

Plain  Sights  to  fit  on  the  Compass  box  or  Telescope,  Astronomical  and 
Diagonal  Eye  Pieces,  Dark  Glass  Caps  for  Sun  observations, — supplied  to  order  at 
an  extra  cost. 


£      s.    d. 

1150  Circumferenter,    or     Miner's    Dial,   4-inch    Ordnance    pattern,    divided 

and  figured  on  raised  rim  to  360°,  and  also  the  quarters  figured  below 
to  90°,  folding  sights,  ball-and-socket  joint  with  clamping  screws, 
bar  needle  and  agate  centre,  the  dial  lettered  the  same  as  a  Theodolite, 
jointed  legs.  In  2  cases  for  compass  and  stand  .  .  .  .770 

1151  Ditto  ditto,  5-inch,  with  Cross  Levels 880 

1152  Circumferenter,    5 -inch,   with   rackwork  adjustment  and    vernier    to  dial, 

bar  needle,  folding  sights,  ball-and-socket  joint,  divided  cover  for  vertical 
angles,  jointed  legs,  complete  in  two  cases  .  .  .  .  .990 

1153  Circumferenter,    6-inch,  with    rackwork    adjustment    and  vernier  to  dial, 

bar  needle,  folding  sights,  divided  cover  for  hypo  and  base,  cross  levels, 
with  tripod  staff,  jointed  extra  points  for  use  at  half  length,  and  ball-and- 
socket  joint  with  plummet,  &c.,  in  two  cases  complete  (fig.  1153)  12  12  0 

45,  CORNHILL,  E.G.,  AND  122,  KEGENT  STEEET,  W.,  LONDON. 



FIG.  1153.  FIG.  1148.  FIG.  1154. 

Circumferenter,  6 -inch,  or  Hedley's  inclining  dial,  improved  form,  folding 
sights,  two  spirit  levels,  bar  needle  with  agate  centre,  rack  adjustment 
to  dial,  two  verniers  reading  to  three  minutes  of  a  degree,  tangent  screw 
adjustment,  divided  arc  for  hypo  and  base,  with  'plain  sights,  complete 
with  ball-and-socket  stand,  joint  legs  for  use  at  half  length,  extra  points, 
plummet,  &c.,  &c.,  in  case  complete  (fig.  1154)  .  .  .  .£17  17  0 

Circumferenter,  Hedley's  Improved,  with  Telescope,  parallel  plates    25    0    0 


Circumferenter,  Lean's  6-inch,  improved,  with  Telescope,  for  surface 
surveying,  centre  quadrant,  with  level,  shifting  sights ;  vernier  reading  to 
two  minutes,  bar  needle,  cross  levels,  rackwork  adjustments,  arc  divided 
on  one  side  90°  each  way  and  on  reverse  for  hypo  and  base,  jointed 
stand  with  extra  points,  &c.  fig.  1155 18  18  0 

17   2 



FIG.  1156.  FIG.  1157*. 

1156  Graphometers  or   Surveyor's  Dials,  7i-mch  divided  circles,  folding  sights, 

level  and  bar  needle  and  circular  spirit  compass,  ball-and-socket  tripod 
stand,  &o.    In  a  mahogany  box  (fig.  1156)  Price         .        .        .  £16  16    0 

1157  Miner's     Compass,    4-inch,    with    folding    sights    in 

mahogany  case £1  10     0        2  10    0 

1157*  Ditto   ditto,    with  Spirit  Levels,  &c.,    mahogany  box 

(fig.  1157)    2  10    0        300 

1 158  Pocket  Mining  Compass,  plain,  with  Sights,  round  brass 

box,  bar  needle,  and  stop  (fig.  1158)    ....  0  16    0 

1159  Ditto  ditto,  in  round  gilt  metal  case,  with  bar  needle, 

and  stop  (fig.  1159)  without  sights      .        .        .  15s.    0  18    0        150 
See  also  Pocket  Compasses. 

FIG.  1160. 

FIG.  1166. 



Surveyor's  Cross,  octagonal  form  (fig.  1160)  . 

Ditto  ditto,  with  Compass 

Ditto  ditto  (or  Pantometre),  with  movable  head 
and  Divided  Circle  and  Compass  (fig.  1162)  of  the  best 
construction • 

Ditto  ditto,  with  Tripod  Stand,  with  ball-and-socket  joint 

Optical  Squares,  for  showing  right  angles     . 

Ditto     ditto,  with  adjustment  in  case    .... 

FIG.  1162. 

£    s.      d. 
0  10    6 


£    s.    c 

0  12 

1  5    i 




45,  CORNHILL,  E.G.,  AND  122,  BEGENT  STREET,  W.,  LONDON.        293 

FIG.  1174.  FIG.  1170. 


1166  Prismatic  Compass  (Kater's),  plain  sights  and  Card  dial  (fig.  1166) 

2-inch,    30s.  2^-inch,    42s.  3-incli,    50s. 

1167  Prismatic  Compass,  3-inch  diameter,  with  Shades  and  Mirror, 

Card  dial,  in  Leather  Sling  Case £330 

1168  Ditto  ditto,  with  engine  divided  Silver  or  Aluminium  ring  and  Case      3  10    0 

1169  Ditto  ditto,  best,  4-inch  with  Sun  Shades,  Card  Dial  and  Case      .440 

FIG.  1170.* 

1170  Prismatic  Compass,  4-inch  best  engine  divided  Silver  or 
Aluminium  ring,  with  Sun  Shades  and  Azimuth  Glass, 
with  Case  (fig.  1170) 550 

1170*  Combined  Altitude  Instrument  and  Prismatic  Compass.  Best 
mounted,  with  Aluminium  divided  Ring,  in  Leather  Case 
with  Straps  (fig.  1170*) 6  10  0 



£     s.    d.  £     s.  d. 

1171  Leather  Case  and  Strap  for  Prismatic  Compass      .        .    0    7     6  0  10  6 

1172  Stand  for  Prismatic  Compass,  best  mounted,  Ordnance  pattern, 

with  ball-and-socket  joint      .         .         .         .        .         .         .  1  16  0 

1173  Ditto  ditto,  plain  horizontal  movement 180 

1174  '  Hutchinson's  Prismatic  Compass,  3-inch,  in  Leather  Sling  Case 

(fig.  1174)  2  10  0 

1175  Tripod    Stand    for    Prismatic    Compass,    with   ball-and-socket 

movement                                                                           .        .  1  12  0 

FIG.  1177. 

FIG.  1177* 

FIG.  1158. 




1  16    0 

Improved  Telescopic  Prismatic  Compass  (figs.  1177,  1177*).  By  it 
both  Vertical  and  Horizontal  Angles  can  be  taken  with  speed 
and  accuracy  Price  in  Mahogany  Box  12  12  0 

Tripod  Stand  for  ditto  with  ball-and-socket  movement  suited  for 
either  of  above  Compasses  ........ 

See  also  Section  Pocket  Compasses. 

Standard  Mountain  or  Surveying  Barometer  (fig.  1179),  on  Fprtin's  principle, 
is  more  portable,  and  less  liable  to  derangement  than  ordinary  Mountain  Baro- 
meters.    The  arrangement  of  the  flexible  leather  cistern  is  so  simple,  that  should  the 
mercury  become  oxidized,  it  can  be  quickly  removed,  cleaned,  and  returned  to  the 
cistern  without  fear  of  affecting  the  correctness  of  the  indications.    The  vernier 
reads  to  *002  of  an  inch,  and  the  whole  instrument  is  arranged  in  a  compact  and 
convenient  form  for  safety  in  travelling,  and  obtaining  the  most  accurate  Altitude 

Price,  including  Tripod  Stand  (as  fig.  1179,  or  fig.  12,  page  13)  and  stout  Leather 
Travelling  Case  for  the  Barometer,  &c  ........  £10  10  '  0 

See  also  pagv  10,  Meteorological  Instruments. 

45,  CORNHILL,  B.C.,  AND  122,  REGENT  STBEET,  W.,  LONDOX.      295 

FIG.  1179. 


1180  Owing  to  the  inconvenient  size  of  Mercurial  Standard  Barometers,  and  also 
from  the  great  risk  of  breakage  in  transit,  it  often  occurs  that  their  use  has  been 
abandoned  by  surveyors  where  otherwise  they  would  have  been  invaluable  for  strict 
altitude  measurements. 

This  difficulty  is  almost  entirely  overcome  by  the  use  of  Negretti  and  Zambra's 
Altitude  and  Surveying  Aneroid  Barometers.  These  instruments  are  now  constructed 
with  such  precision  that  very  small  elevations  may  be  ascertained  with  great  exacti- 
tude. The  scale  of  the  altitude  aneroid  is  laid  off  by  actual  experiment  in  a  vacuum 
chamber,  the  readings  being  noted  both  backwards  and  forwards,  such  readings 
being  repeated  at  long  intervals,  and  the  observed  differences  corrected,  before 
finally  dividing  the  scale  on  the  dial.  Several  tests  are  also  applied  to  the  instrument 
in  order  to  compensate  for  errors  arising  from  varying  extremes  of  temperatures. 

Where  it  can  be  conveniently  carried,  Negretti  and  Zambra  would  in  all  cases 
recommend  their  full-sized  Altitude  Aneroid  (fig.  1180)  for  observers'  use ;  as  from 
the  large  diameter  of  the  divided  circle,  exceedingly  minute  movements  of  the 
index  hand  may  be  seen  with  ease. 



FIG.  1180.  FIG.  1184. 

Should  it  be  that  the  large  Aneroid  cannot  be  carried,  Negretti  and  Zambra 
can  with  confidence  advise  the  use  of  their  Watch-sized  Aneroids  with  altitude 
scales.  The  exact  size  of  these  instruments  is  shown  at  page  19.  A  large  number 
of  such  small  Aneroids  having  been  made  by  Messrs.  N".  and  Z.,  and  reports 
received  of  (their  wonderfully  'accurate  performance  in  all  parts  of  the  world, 
warrant  N.  and  Z.  in  giving  the  strongest  recommendation  to  them.  At  page  3 
and  26  will  be  found  instructions  for  measuring  heights  by  the  Aneroid,  and 
comparative  tables  of  the  French  and  English  scales. 

A  copy  of  Professor  Airy's  Altitude  Tables  supplied  with  each  instrument. 
1180  Negretti  and  Zambia's  full  range  Altitude  and  Surveying  Aneroid 
Barometer  (Orometer),  Compensated  for  temperature,  the  Scale 
divided  to  Inches  and  Hundredths  or  Millimetres,  with  Altitude 
Scale  to  20,000  feet,  or  about  15  inches  of  the  barometer  scale 
(fig.  1180)  in  hinged  leather  case  .......  £880 

Solid  leather  case  with  Sling  strap  for  Ditto    .....    0  12    6 

1181  Pocket  Aneroid  Barometer,  with  Altitude  Scales  to  5,000  feet, 

moderate  elevations  ;  see  ante,  page  29  (fig.  24)     .        .        .        .550 

1182  Watch-sized   Pocket    Aneroid    Barometers,    Compensated   with 

Altitude  scale  to  10,000  feet;  see  ante,  page  24  (fig.  26)        .        .550 
Ditto  ditto,  to  20,000  feet  ........    660 

Ditto  ditto,  to  ditto  in  Stout  Silver  case  .  .  .770 

Aneroid  Barometers  with  adjusting  altitude  scales  10s.  each  extra. 

1183  Anemometer,  Pocket,  Biram's,  and  Lown's,  for  registering  the 

velocity  of  currents  of  air  in  mines,-  air  shafts,  drains,  &c.,  &c. 
For  full  description  and  instructions  for  use,  see  pages  100  to  103. 

4-inch  size,  £2  10s.  ;  2^-inch    .        .        .  .220440 

1184  Surveyor's  Pocket   Compass,  with  Bar  Needle  or  Singer's  Card 

Dial,  in  Silver  Watch  Case  (fig.  1184)    ....    £2  10s.    330 
See  also  Section  Pocket  Compasses. 

45,   CORNHILL,    E.U.,   AND   122,    REGENT   STREET,    W.,    LONDON. 


FIG.  1185. 

1185  Perambulator,  for  measuring  the  length  of  roads,  streets,  &c.,  consists  of  an 
accurately  framed  Mahogany  Wheel,  Brass  Clamped,  the  circumference 
of  which  is  carefully  ascertained ;  the  axis  of  this  Wheel  is  connected 
by  a  series  of  toothed  wheels  and  pinions  to  a  dial,  upon  which  the  number 
of  revolutions  of  the  Wheel  are  recorded.  The  divisions  upon  the  dial  are 
English^  Measures ;  but  any  Foreign  scale  can  be  substituted  to  order. 
Price,  Best  mounted  and  finished  (fig.  1185)  .  .  .  £16  16  0 

FIG.  1186. 

FIG.  1190. 



Trocheameter,  Negretti  and  Zambra's  Improved  construction  for 
registering  the  revolutions  of  a  Carriage  Wheel  and  by  this  ascertaining 
distances  travelled ;  it  is  also  applicable  for  counting  the  revolutions  of  fly 
wheels,  paddle  wheels,  &c.,  up  to  10,000  revolutions,  or  nearly  23  miles 
distance,  travelled  by  a  coach  wheel  of  12  feet  circumference.  These 
numbers  can  be  repeated  by  re- setting  the  instrument,  which  is  very  easily 
done,  by  removing  a  nut,  and  turning  back  the  divided  wheels  to  the 
0  point.  The  Trocheameter  is  contained  in  a  strong  case,  with  a 
leather  strap  for  attaching  it  to  the  wheel,  &c.  (fig.  1186)  .  £330 

The  Dipleidescope.f  A  Pocket  instrument  for  obtaining  the 
Correct  Time  with  great  facility,  by  observing  the  Transit  of  the 
•Sun  across  the  Meridian  *  best  form  £10  10  0 

t  See  also  N.  &  Z's.  Improved  Transit  Instruments,  page  254. 



FIG.  1187. 

FIG.  1187*. 

1187  Pedometer  or  Watch  for  Recording  and  Measuring  the  distance  travelled  by 
a  Pedestrian. 

This  little  instrument  is  generally  carried  in  the  waistcoat  pocket  or  in  the 
fob,  or  else  attached  to  a  belt  or  to  a  button ;  the  hook  attached  to  the  ring  must 
be  so  fastened  to  the  slit  of  the  pocket  or  elsewhere  that  the  instrument  be  always 
in  a  Vertical  Position. 

It  never  requires  any  winding  up,  the  first  step  of  the  Pedestrian  sets  the 
works  in  motion ;  they  continue  to  act  as  long  as  he  moves,  and  stop  when  he 
stops.  The  dial  is  divided  into  twelve  divisions,  which  represent  so  many  Miles, 
but  can  be  adapted  to  record  Kilometres  or  any  other  measure  of  distance.  The 
Pedometer  is  corrected  by  means  of  an  adjusting  screw,  which  is  square -headed,  so 
as  to  be  turned  by  a  watchkey  ;  all  that  is  necessary  to  do  is  to  walk  a  mile,  and  then 
observe  the  position  of  the  index  hand  upon  the  dial ;  the  regulator  is  then  turned 
to  the  left  for  Slow,  or  to  the  right  for  Fast,  until  one  division  on  the  dial  represents 
exactly  the  measure  of  distance  chosen,  Mile  or  Kilometre,  &c.  This  of  course  will 
depend  upon  the  length  of  stride  of  each  individual,  and  must  be  regulated  accord- 
ingly. The  dots  between  the  figures  represent  Quarter  miles.  When  about  to 
start,  the  Index  Hand  should  be  placed  at  Zero,  by  moving  it  either  backwards  or 
forwards  with  the  finger.  If  the  Pedometer  is  not  required  to  act,  it  should  be 
carried  with  the  Pendant  ring  downwards. 

FIG.  1187  exhibits  the  dial  or  face  of  the  Pedometer,  and  fig.  1187*,  the  interior 

and  movement  of  the  instrument.      Price,  in  Stout  Silver  with  case     .      £2  15     0 

Ditto  ditto  Price,  in  Nickel  Plated  with  case  .        220 

Ditto  ditto  Price,  in  German  Silver  with  case         110 

1188  Passometer  or  Step  Measurer,  is  a  similar  sized  instrument  to  the  Pedometer, 
arranged  to  record  the  number  of  paces  or  steps  taken  by  the  wearer.     These  are 
indicated  on  the  face  of  the  instrument  by  a  small  circle  (similar  to  the  seconds 
dial  of   an  ordinary  watch)   up  to  50,  and  then  on  the  large  dial  by  a  series  of 
divisions,  each  equally  50  paces  up  to  2,500 ;  the  readings  on  the  dial  are  continuous 
as  in  the  Pedometer.  Price,  in  Stout  Silver  Case    .         .£550 

1189  Chronograph.   Without  stopping  the  movement  of  the  watch  the  long  seconds' 
hand  of    this  instrument  records  on  the  Dial    the  interval  between  two  given 
events,  with  unfailing  accuracy.    Price,  in  Gold  Case,  60  guineas ;  Silver  Case, 
45  guineas  ;  or  to  go  for  two  hours  only,  Gold,  £20,  Silver  £12  12s. 

45,    CORNHILL   B.C.,   AND    122*  REGENT    STREET,   W.,    LONDON-. 


Fm.  1197.  FIG.  1201. 

1190  Current  Meter,  for  ascertaining  the  tidal  rate  or  flow  of  streams  or  rivers, 

in  Miles,  Furlongs,  and  Feet ;  the  amount  of  Water  delivered  per  hour 
in  Cubic  Gallons  and  inches ;  and  the  Dynamic  force  of  the  Current.  This 
instrument  can  also  be  .used. as  a  Log,  to  determine  the  rate  of  a  ship's 
speed.  The  scales  on  the'divided  wheels  are  laid  off  by  careful  experiment 
(fig.  1190).  Price  in  mahogany  box  .  .  .  .£660  770 

1191  4-inch  Pocket  Inclinometer,  Brass  mounted,  with  Sights  and  Graduated  Arc 

for  determining  the  inclination  of  strata,  &c.,  with  socket  for  staff ;  in 
mahogany  box  (fig.  1191)  , 3  10  0 

FIG.  1191. 

1192  Clinometer  or  Inclinometer,  12-inch,  plain  boxwood,  with  divided 

semi-circle  and  plumb,  for  ascertaining  the  inclination  of 
roads,  drains,  strata,  &c.,  in  a  rough  way.  The  divisions  on  the 
arc  show  degrees  and  inches  per  yard  ;  it  has  also  an  inclination 
scale.  Price,  in  pull-off  case 0  16  6 

1193  Clinometer,  12-inch  boxwood,  brass  jointed,  with  divided  arc  and 

inclination  scale,  forming  a  pocket  rule        .  ...       1     1     0 

1194  Clinometer,  6-inch,   plain-jointed,   without    Sights  or 

Compass        .........  110 

1195  Clinometer,    6-inch,     with    Spirit    Level,     Magnetic 

Compass,  and  Inclination  Scale 1  18     0        220 

1196  Ditto  ditto,  Bar  Needle  Compass,  and  two  levels  .        .  2  10    0 

1197  Ditto  ditto,  with  best  Bar  Needle  and  Agate  Centre 

Compass  in  the  joint  (fig.  1197)  .....  330 

The  inclination  scale  placed  upon  these  Clinometers,  &c.,  gives  the  value  of  any  angle,  as  follows , — 
The  angle  having  been  ascertained  from  the  divided  arc  upon  the  instrument,  refer  to  that  degree  in  the 
column  marked  Angle,  and  opposite,  in  another  column,  will  be  found  the  rise  or  fall  in  any  given  measured 
distance ;  for  instance,  say  the  degree  shown  on  the  divided  arc  is  18,  opposite  to  this  number  on  the 
scale  is  3,  this  indicating  one  part  rise  or  fall  in  three,  or  one  mile  in  three  miles,  one  t'oot  in  three  feet,  &c. 


1198  Geological  Compass,  for  ascertaining  the  dip  or  inclination  of  strata,  hills, 

&c.,  with  index,  in  degrees  and  inches  per  yard,  in  mahogany  box,  4|  inches 
square  ...;., £0  10     6 

1199  Ditto        ditto,     3  inches  076 

1200  Ditto        ditto,    2|  inches •     .  070 

1198io  1200,  if  with  best  Bar  Needles,  2s.  6d.  each  extra. 

1201  Geological  Compass,  Brass  mounted,   with  best   Bar 

Needle  and  leather  case  (fig.  1201)      .        .30s.    42s.    2  10    0        3  10    0 

FIG.  1202. 

1202  Pocket  Alt-Azimuth  Instrument,  improved  by  Francis  Galton,  Esq.,  F.RS., 
is  a  combined  Compass  and  Pendulum  or  Wheel  Clinometer.  A  most  convenient 
and  portable  instrument  for  obtaining,  in  a  ready  manner,  Angles,  Levels,'  &c., 
similar  to  No.  1170*.  The  Telescope  renders  this  instrument  available  for 
observing,  at  a  considerable  distance  from  the  Station,  either  Magnetic 
Bearings,  Horizontal  or  Yertical  Angles,  &c..  &c. 
Price  in  case,  as  fig.  1202  ....  £660 

Pocket  Alt-Azimuth  without  Telescope 5  10    0 

Our  woodcut  shows  the  Clinometer  side  of  the  instrument,  with  the  Telescope 
as  drawn  out  for  use 

1202*  Hydroscope  or  Telemeter,  a  simple  apparatus  constructed  by  Negretti  and 
Zambra  for  the  Government  Ordnance- Department  for  use  in  Marine 
Forts,  to  estimate  the  distance  of  vessels  and  other  objects  .  500 

45,    COBNHILL,   E.G.,   AND    122,    EEGENT   STEEET,   W.,   LONDON 


FIG.  1203. 

1203    Abney's  Contouring  Reflecting  Level  or  Pocket  Altimeter.    Improved  form 
with  divided  arc  to  show  gradients,  &c.,  (Fig.  1203).  Price  in  case      .        £220 
Fig.  1202  and  Fig.  1203  are  very  nearly  the  actual  size  of    the  instruments 
described  above. 

FIG.  1215. 

FIG.  1209. 

FIG.  1216. 






Land  Chain,  Iron,  50  feet,  and  10  Arrows 

Ditto,  ditto,  100  feet,  and  10  Arrows      .... 

Land  Chain,  100  feet,  best  Steel  Wire  with  ditto  . 

Gunter's  Iron  Measuring  Chain,  sixty-six  feet,  or  four 
poles  in  length.  Light  wire  ..... 

Ditto  dito,  Stouter,  Galvanised 

Gunter's  Iron  Measuring  Chain,  lest  quality,  Steel  Wire, 
with  three  sawed  oval  rings  between  each  link,  and 
swivel  in  middle,  and  stout  Brass  swivel  handles  and 
marks— Galvanized  (fig.  1209) 

Twenty-metre  Chains,  Centimetre  links,  best  make 

Arrows,  set  of  Ten  Steel  wire,  Pointed  and  Numbered 
for  Ditto,  15  inches  long  and  If -inch  eye  . 

Standard  Chain,  50 -feet,  best  stout  Steel  Wire     . 

Ditto        ditto        66-feet 

Ditto        ditto        100-feet 

0  11 

0  14 

1  2 

0  12 
0  15 

0  18  6 
0  18  6 

4  10  0 
8  10  Q 



1214  Measuring  Tapes,  common,  Leather  cases  : 

Length  .        :       33-feet.  50-feet.  66-feet.  100-feet. 

Price         .        4s.  5s.  6d.  6s.  6d.  10s.  6d. 

1215  Measuring   Tapes,    in  japanned    Leather  eases,    with  folding 

handle,  rollers,  &c.:-(fig.  1215.) 

Length  .        .       33-feet.  50-feet.  66-feet. 

5s.  6d. 

6s.  6d. 


Fig.  1225. 




0  12 

Price  . 

1216  Best  Measuring  Tapes,  in  Best  Patent  Solid  Leather  Cases, 

Black  |or  Brown,  folding  handles,  rollers,  scale   marked  on 
one  side  only    (fig.  1216.) 

Length       .     33-feet.  40-feet.  50-feet.  66-feet.  100-feet. 

Price      .        8s.  9s.  10s.  6d.          11s.  6d.          15s. 

1217  Best  Measuring  Tapes,  as  No.  1216,  with  English  and  Metre 

Scales,  or  English  and  Varas.     (fig.          ). 
Length       .     10-feet.  15-feet.  20-feet.  25  30-Metres. 

Price      .     8s.  6d.          9s.  6d.         12s.  6d.  14s.       .     16s.  6d. 

1218  Patent  Elastic  Steel  Tapes,  leather  case,  flush  handles, 

marked  on  both  sides— 33-feet,  or  2  poles,  24s.  50-feet  £1  15 
66-feet,  or  4  poles,  45s.  100-feet    3    3 

Patent  Pocket  Spring  Measuring  Tapes,  in  Brass  Case, 
(fig.  1219)  3-feet        2s.  6d.,  036 

6-feet        5s.  6d.,  076 

Patent  Elastic  Steel,  ditto— 3-feet       .... 
(fig.  1220)  6-feet        .... 

9-feet        .... 

Pocket  Spring  Tapes,  in  German  Silver  Cases,  with  stops 
and  rollers,  English  yard,  and  French  metre, 
3-feet,  6-feet,  and  9-feet       .       4s.,     5s.  6d.,     7s.  6d.     0  10    6 

1222  Measuring    Tapes  made  to    order  with   French,   Spanish    or 

Portuguese  and  other  Scales  in  various  lengths  and  mountings. 

1223  Levelling  or  Station  Staff,  common  form       .        .        .    1  10    0 

1224  Sopwith's  Station  Staff,  14-f eet  improved  three-jointed, 

"best  socket  fittings,  each    220   'per  pair    440 

1225  Ditto      ditto,     best    Painted  scale,  sliding  in  three 

lengths,  put  together  with  brass  screws,  mountings 

and  springs  (fig.  1225)  each    2  12    6    per  pair    550 

1226  Ditto  Ditto,  Metrically  divided,  same  price  as  above. 

1227  Station  Staff,  14  feet  three-joint  half-round  Ordnance 

pattern,  per  pair .        .        .        .        .        .        .        .     7  10    0 

1228  Levelling  Staves.     Lieut.-Col.  Strange's  arrangement. 

The  foot  is  divided  into  alternate  black  and  white  spaces,  each  representing 
half  a  tenth  of  a  foot.  All  the  figures,  both  those  indicating  the 
feet  and  those  indicating  tenths  of  a  foot,  are  on  the  same  side  of  the 
scale.  The  object  of  this  is  to  obtain  more  ground  surrounding  the 
figures,  as  on  this  condition  their  visibility  in  a  great  measure  depends. 

The  forms  of  the  figures  have  been  carefully  studied.  The  figures  denoting 
tenths  of  a  foot,  are  small.  It  was  found  that  those  usually  employed 
are  needlessly  large.  The  size  now  adopted  is  the  result  of  trial  at 
10  chains,  at  which  distance  they  can  be  easily  read  with  a  good 
14-inch  'Telescope.  Price  per  pair,  £880 

45,  CORNHILL,  B.C.,  AND  122,  KEGENT  STREET,  W.,  LONDON. 


1229  French  Pattern  Station  Staves,  4-Metres  long  with  plain  metal    £    B.  a. 

mountings per  pair    440 

1230  Ditto    ditto,  5-Metres,  fully  divided  scale,  and  inverted  figures  with 

best  brass  mountings       .        .         .        .        .        .         .        •        .550 

1231  Papers  for  Level  Staves, per  foot    003 

FIG.  1241. 

FIG.  1242. 


1232  24-inch  Scale,  Boxwood,  25  inches  long,  If  broad,  square  at  the 

edges,  having  1  and  2-inch  diagonal  scales  on  two  edges,  the  inch 
in  tenths  and  eighths,  the  foot  into  decimal  parts,  and  a  scale  of 
chords  to  a  radius  of  12-inches  to  be  used  with  Beam  Compasses  0  10  6 

1233  Architect's  Scale,  Boxwood,  12i-inches  long,  l£-inch  broad,  and 

the  inch  and  half -inch  to  a  foot  on  one  edge,  and  the  quarter  and 

three  quarters  to  the  foot  on  other  edge 040 

1234  Surveying  Scale,  Boxwood,   12J-inches  long,  1^-inch  broad,  and 

chamfered  alternately,  with  diagonal  scales,  and  scales  on  the 

edges,  also  scales  of  yards  and  paces  to  2,  4,  and  6  inches  to  a  mile    040 

1235  10-feet  Rod,   l|-inch  square   deal  painted,  divided  into  feet  and 

quarters  on  all  sides,  and  figured  from  both  ends  alternately,  shod 

with  brass .         .         .100 

1236  Link  Staff,  li-inch  square,  deal  painted  black,  divided  into  10  links 

on  all  sides,  the  centre  division  marked  with  a  star,  shod  with 

brass 0  12     6 

1237  5-feet  Surveyor's  Measuring  Rods,  lance  wood,  tipped  with  brass, 

divided  on  one  side  into  feet  and  quarters,  and  on  the  other  into 

feet,  inches,  and  one-eighths 086 

1238  2-feet  Rule,  Boxwood,  4-fold  Gun  and  Shot  Gauge,  and  the  inch 

divided  into  10,  8,  and  12  parts 0  12     0 

1239  Standard  Measure,   Yellow  Dial,   43  inches  long,  24-inch  wide, 

I -inch  thick,  with  edge  bar  along  the  middle,  with  four  brass  plates 
let  in;  on  the  top  and  edge  of  one  side,  3  standard  feet  are 
accurately  marked  off,  and  on  the  other  sides  two  brass  plates 
marked,  5  standard  links.  In  a  deal  case 1  10  0 



1240  Levelling  Staff,  14-feet,  mahogany  sliding  in  3  lengths,  with  brass    £    a.    d. 

spring  and  fittings,  Painted  Scale,  per  Pair  £550  see  No.  1225. 

1241  Protractor  Semicircular,  brass,  6-inch,  figured  to  180°  and  to  360^. 

The  arm  6^-inch  long,  with  vernier  reading  to  minutes  with  clamp 
screw,  and  magnifying  glass  in  mahogany  case,  both  sides  of 
the  arm  parallel  to  the  centre  and  zero  (fig.  1241)  .  .  ,330 

1242  Protractor  Plain  Circular,  brass,  8-inch,  figured  outside  to  360°,  and 

inside  each  quarter  to  90°,  divided  to  half-degrees.  In 
mahogany  case  (fig.  1242) 220 

FIG.  1243. 

1243  Beam  Compass,  Mahogany  beam  inlaid  with  holly,  graduated  to 

50  inches,  vernier  reading  to  -^  inch,  48  inches  between  the  points, 

ink  and  pencil  points  and  clamping  screws,  in  deal  case  (fig.  1243)     3  12    6 

1244  T  Square,  mahogany,  12  by  25  inches  having  the  stock  and  blade 

flush  on  one  side 0  12    0 

1245  Ditto  ditto  12  by  52-inch 0  16    0 

1246  Angles,  6-inch,  pear-tree,  Set  Square  45° 020 

1247  Ditto      9-inch        ditto        ditto       30° 030 

1248  Straight  Edge,  Steel,  best  London  make,  2  inches  wide,  42-inch, 

in  deal  case 140 

1249  Ditto  ditto  ditto  52 -inch,  in  ditto       .        .        .  1  10    0 

1250  Parallel  Rules,  15-inch,  best  Ebony  rolling,  plain  edges   .        .        .  0  16    6 

1251  Ditto      ditto    12-inch      ditto      ditto 0  12    6 

1252  Ditto      ditto      9-inch       ditto      ditto 0  10    6 

1253  Chain  100  feet  with  3  oval  rings  between  each  link,  stout  brass 

marks,  best  stout  iron 120 

1254  Ditto    ditto  four,  Pole  Gunter's        .        . ' 0  18    6 

1255  Arrows,  set  of  10  by  14-inch,  If -inch  eye 020 

1256  Dark  Glass  Horizon,  in  Brass  Frame  with  3  adjusting  screws  and 

Spirit  Bubble  ground  on  one  side,  in  Mahogany  Box    .        .        .250 

1257  Centrolinead,    for    drawing    buildings,    &c.,    in    perspective,  the 

instrument  giving  the  line  of  direction  of  the  vanishing  point     .330 

1258  Elipsographs,  for  striking  Ovals 330550 

1259  Ditto        ditto,  German  Silver 4  12    6 

1260  Planimeter,  Amsler's  Patent  Brass  for  computing  areas  .        .        .    3  15     6 

1261  Integrator,  Ansler's 18    0    0 

1262  Goniometer,  Wollaston's  Reflecting,  for  measuring  the  Angles  of 

Crystals    .        .        ..        . 550 

1263  Eidograph,  capable  of  reducing  any  proportion  from  1  to  6  inches 

in  box  complete       .        .        .        .      £11    0    0    £12  12    0  and  15    0    0 

1264  Computing  Scale.     Universal,  as  used  by  H.M.  Tithe  Commission 

Office,  containing  1,  2,  3,  4,  5,  6  chains  to  the  inch,  and  6  inches 

and  5  feet  to  the  Mill  in  Mahogany  box 3  12     0 

1265  Extra  Scales  fitted  to  above 056 

1266  Computing  Form  Papers,  10,  20, 30,  40,  50,  or  60  per  sheet      .        .050 

45,   COBNHILL,    E.G.,   AND    122,    REGENT   STREET,     W.,    LONDON. 


FIG.  1266. 

1266*  Pentagraph  or  Pantograph,  in  Brass,  of  the  best  construction,  for  ^ 

reducing  or  enlarging  plans  to  any  proportion  : —  £   s.   a. 

18-inches from    660 

24-inches 7  10    0 

30-inches,  Ordnance  size  and  Pattern  with  improved  Leg 

and  Wheel 9  10    0 

36-inches 10  10    0 

42-inches 11  11     0 

48-inches  (fig.  1266) 13  10    0 

1277  Pentagraph,  Ebony     ........         from    550 

1278  Ditto,  common  White  Wood     .        .        .        .  .      10s  6d.    1    5    0 

FIG.  1280. 

FIG.  1283 


Opisometer  or  Map  Meter,  for  measuring  Curved  lines  on  Plans  or 
Charts,  &c 036 

1280  Ditto  ditto     Improved,  (fig.  1280)  .        .        .        .       4s.  6d.    0    5    6 

1281  Chartometer    for    measuring    and    registering    distances    on    Maps.     The 
Chartometer  is  about  the  size  of  a  watch,  with  a  small  wheel  partly  projecting  from 
the  lower  end  of  the  case.     To  measure  any  line,  the  instrument  is  held  upright, 
and  the  little  rolling  wheel  is  run  along  the  line  to  be  measured ;  as  the  wheel 
advances  an  index  hand  registers  on  a  dial  the   distance  passed  over  in  miles, 
yards,  &c.,  according  to  the  scale  of  the  map.    It  can  be  used  for  maps  of  different 
Scales  by  a  simple  substitution  of  one  dial  plate  for  another,  a  variety  of  those 
adapted    to    the  ordnance  measurements  being  contained  in    the  case  of    the 

1282  Chartometer  with  Set  of  Dials,  in  neat  Leather  Case      .        ..110 
Ditto        ditto     German  Silver  Plated,  complete  in  Case  (fig.  1283)     1  12    0 
Ditto        ditto    Gold  plated  best  finish,  complete  in  Case       .        .220 
Wealemefna,  a  Pocket  Instrument  for  measuring  lines  or  distances 

on  a  map,  Nickel  Plated,  7s.  6d.,  [10s.   6d. ;  Silver,  10s.  6d.,  and 
12s.  6d. ;  Gold  ditto,  30s.  and  50s. 

For  further  particulars  of  Drawing  Instruments,  Rules,  Scales,  &c.,  see  Section 
Mathematical  Drawing  Instruments. 






Metal  Sextant,  in  Mahogany  Box  £8    8s.  or  £10  10s. 

Achromatic  Telescope,  1  draw  £2  10s.  • 

Ditto  ditto,  German  Silver  Mounted  £3    3s. 

Ebony  Parallel  Rule,  18-inch,  best,  6s.  6d. 
Mathematical  Drawing  Instruments,  Brass  complete,  with   Rules  and  Scales,  in 

polished  Mahogany  Box  £2  15s.  and  £3  10s. 

Ditto  ditto  ditto,  German  Silver  £4  10s.          £5    5s. 

Binocular  Look-out  Glass,  in  solid  Leather  Case,  with  Strap,  £4  4s.  and  £5  5s. 



Best  Pocket  Sextant  with  Telescope,  Silver  Arc,  &c.,  in  Leather  Case  with  Sling 
Strap,  as  No.  1303.  £5  5S. 

Best*  Prismatic  Compass  with  Sun  Shades  and  Azimuth  Mirror,  in  Leather  Case, 
with  Sling  Strap,  as  Nos.  1167  and  1170  £3  3s.  and  £5  5s. 

Sketching  Protractor  7s.  6d. 

50-feet  best  Tape  Measure,  as  No.  1216  12s.  6d. 

18-inch  Ebony  Parallel  Rule  6s.  6d. 

Binocular  Field  Glass  in  solid. Leather  Case,  with  Strap,  £4    4s.  and  £5    5s. 

Achromatic  Reconnoitring  Telescope  £3  10s.  and  £4    4s. 

Mathematical  Drawing  Instruments,  Brass,  with  Rules  and  Scales,  Mahogany  Box, 

£3  10s. 

Ditto  ditto  ditto,  German  Silver  £4    4s. 

Scales,  Rules,  Tapes,  and  Chains  made  to  all  Foreign  Measures  to  order. 

Heliographs  for  Military  Signalling,  Universal  Sun  Dials  both  for  North  and 
South  Latitudes,  Improved  Binocular  Telescopes,  Aneroid  Barometers  for  Altitude 
Measurements,  &c.,  &c.,  see  the  various  sections  in  this  Catalogue. 

45,    CORNUILL,   E.G.,   AND   122,    REGENT   STREET,   W.,    LONDON.  307 




A  5-incli  best  Theodolite,  divided  on  Silver,  with  Tripod  Stand,  as  fig.  No.  1100,  £24 
A  15 -inch  Dumpy  Y  Level,  with  ditto,  ditto,  as  fig.  No.  1130  £18  18s. 

Pocket  Compass,  3£  square,  mahogany  box.     2  circles  of  divisions,  one,  360°,  the 

other  figured  4'90°.    Best  bar  needle,  16s. 
Surveying  Cross,  round,  on  Ash  staff,  as  fig.  No.  1160,  12s.  6d. 
Drainage  Level,  with  Tripod  Stand,  fig.  1134  £5     5s. 

A  4-inch  Circumferenter,  folding  sights,  ball  and  socket  joint,  with  jointed  tripod 

stand,  as  No.  1150  £7    7s, 

Ordnance  Pattern  Drawing  Boards  : — 

Antiquarian      .      55  by  33  inches.  Atlas     .        .     37  by  28  inches. 

Double  Elephant    43  by  29      „  Imperial        .    32  by  24      „ 

Prices  various. 
Prismatic  Surveying  Compass.     3-inch  card,    with    Silver   ring,  in   Pocket  case, 

as  No.  1168  £3  10s. 

Best  Pocket  Sextant  with  Telescope,  divided  on  Silver  arc  with  Leather  Case  and 

Strap  as  No.  1303  £5    5s. 

100  feet  best  Stout  Chain,  Brass  handles,  &c.,  as  No.  1206  £1    2s. 

4-pole  best  Gunter's  ditto  ditto,  as  No.  1209  18s.  6d. 

1  set  10  14-inch  Arrows  with  eye  If  inch  diameter  as  No.  1210*,  3s. 
1  case  of  Brass  Drawing  Instruments  : —  £2  10s.  and  £3    3s. 

Mahogany  box  with  Tray  containing  6-inch  ivory  scale,  6-inch  ebony  parallel  rule, 

6-inch  compasses  with  pen  and  pencil  points,  lengthening  bar,  pen  and  pencil 

bow,  large  and  small  ivory  handle  drawing  pens,  set  screw,  6  drawing  pins,  &c. 

£3    3s. 

Best  Mercurial  Horizon,  complete  in  box  £4  10s. 

6 -inch  Sextant  divided  on  Silver  to  10  seconds,  with  plain  tube,  two  Telescopes  with 

additional  power  and  dark  glasses  in  mahogany  case, 

£10  10s.  and  £11  11s. 

Tripod  Stand  for  ditto,  with  jointed  legs  £3    3s.  and    £5     5s. 

30-inch  brass  Pentagraph,  as  fig.  1266,  in  mahogany  box  £10  10s. 

Mountain  Barometer  in  solid  Leather  case  and  brass  stand,  as  No.  1179,  £10  10s. 
Aneroid  Barometer  or  Orometer,  as  No.  1180  for  Altitude  measurements,  £8  8s. 
Pocket  Thermometer,  Oval  Boxwood,  7-inches  long,  0  to  l40°  Fahrenheit  and 

Centigrade  Scales     ....     See  also  Section  Thermometers     12s.  6d. 
Altitude  Tables  for  use  with  above,  sent  with  each  instrument. 
Boiling  Point  Apparatus  and  Tables,  see  page  92. 



FIG.  1290. 

£     s.    d. 

1589    Reflecting  Circle  (Troughton's  Pattern)  10-inch      .        .        .        .    25    0    0 
1290    Ditto  ditto,  12-inch  (fig.  1290)  .        .        .        .    30    0    0 

This  instrument  perfectly  corrects  the  error  of  the  centre  by  the  readings  of 
the  three  branches  of  the  index ;  this  property,  combined  with  that  of  observing 
both  ways,  reduces  the  errors  of  dividing  one-sixth  part  of  their  simple  value.  With 
this  Circle  angles  may  be  measured  as  far  as  one  hundred  and  fifty  degrees. 

1291  Ebony     Sextant,      8-inch,      best,    with     Ivory     arch 

Achromatic  Telescopes,  &c.,  in  mahogany  case  .  6  10     0 

1292  Metal  Sextant,  6-inch  (Cadets')  Circular  pattern,  divided 

on  Silver  reading  to  ten  seconds,  three  Telescopes,  in 

mahogany  case  (fig.  1292) -      .  880 

1293  Metal  Sextant,  best,  5-inch  (Cadets')  Triangular  pattern, 

divided  on  Silver,  reading  to  10  seconds  extra  power 

to  Telescope,  strapped  horizon  adjustments  in  Box    .  990 

1294  Metal  Sextant,  8-inch,  Edge  Bar  Pattern,  bronzed  limb 

divided  on  Silver,  reading  to  ten  seconds,  in  mahogany 

box 10  10    0 

1295  Metal   Sextant,   8-inch,   Oval    pattern,   bronzed  limb 

divided  on  Silver  reading  to  ten  seconds,  stump  and 

block  adjustment  and  glass  reflector  to  vernier  .  11  11     0 

1296  Metal  Sextant,  Oval,  Triangular,  or  other  patterns,  best, 

bright  or  bronzed  limb,  Neutral  Tint  Shades,  and 
extra  power  for  Telescopes,  Glass  Reflector,  &c.,  in 
square  polished  mahogany  case  with  screwed  fittings  12  12  0 

45,    COBNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON.  300 

FIG.  1297. 

FIG.  1292. 

FIG.  1297*. 


Metal  Sextant,  8-inch,  Best  Edge  Bar  or  Triangular  Pattern  bridge  handle 
divided  on  Silver  reading  to  ten  seconds,  bright  or  bronzed  limb,  cup 
and  ball  tangent  screw,  swing  horizon,  and  capped  adjustments,  Neutral 
Tint  Shades,  and  extra  power  to  Telescopes,  and  of  the  most  accurate 
finish,  and  with  all  recent  improvements,  in  square  mahogany  case 
(figs.  1297  or  1297*) Price  £13  13  0 

1298  Lunar  Sextant,  I-inch,  best  make,  bridge  handle,  triangle  pattern.     Extent 

of  arch  150  degrees.  Yernier  reading  to  ten  seconds,  with  excess  divisions, 
strapped  and  capped  adjustments,  Neutral  tint  shades ;  large  size 
Telescopes,  with  extra  power ;  star  telescope ;  magnifier,  &c.  In  square 
mahogany  box,  with  lock  and  key 14  14  0 

1299  Gold  or  Platinum  Arch  to  either  of  above 2  12    0 

1300  Tripod   Stands  for  Sextants,  with   jointed  legs,  horizontal    and   vertical 

action  and  clamping  screw,  in  deal  case       .        .        .        .        .        550 

Quadrants  or  Octants  and  Sextants  can  be  supplied  of  an  inferior  quality,  at  slightly 
lower  prices,  but  they  cannot  be  recommended. 



FIG.  1301. 




Pillar  or  Double  Platecl  {Sextant,  8-incli,  reading  to  ten  seconds,  with  addi- 
tional power  to  telescope  and  Reflectors  to  verniers,  &c.,  of  the  very  best 
quality,  in  Best  Square  Polished  mahogany  case  (fig.  1301)  .  £17  17  0> 


FIG.  1303. 

Pocket  or  Box  Sextant,  with  Back-work  adjustment     . 

Pocket  Sextant,  best  quality,  divided  on  Silver,  with 
Telescope  and  Tangent  adjusting  screw,  &c.  (fig.  1303), 
with  leather  case  and  strap 

Ditto,  ditto,  with  Cover,  divided,  hypo  and  base   . 

Horizon  Glasses,  for  Quadrants      .        .        .    pei  doz. 

Index        ditto  for  ditto  .  ... 

Coloured  Shades,  for  ditto      .       .       .       per  set  of  7 

Horizon  Glasses  for  Sextants          .        .        .    per  doz. 

Index  Glssses    for  ditto 

Neutral  Coloured  Shades,  best  parallel,  per  set  of  7 

Sets  of  3  Achromatic  Telescopes  for  Sextants,  best 

Extra  Power  for  ditto 

Star  Telescopes  for  Sextants  ...... 

Horn  (Index)  Magnifiers         .       .       .       .per  doz. 


5  15  0 
0  12  0 
0  14  0 

1  10 

2  2 


0  15  0 
0  15  0 

45     COENHILL,   B.C.,    AND    122,   KEGENT    STREET,    W.,    LONDON. 

FIG.  1316. 

FIG.  1315. 

FIG.  1320. 


1315  Ebony  Quadrant,  with  Tangent  screw  to  index,  in  oak 

case  (fig.  1315) 

1316  Ditto  ditto  with  two  Tangent  screws,  and  bar  to  index 

and  vertical  screw  (fig.  1316) 

1317  Ditto  ditto  ditto,        with  six  shades     . 

1318  Telescope  with  shutter  to  above,  extra    .... 

1319  Ebony  Quadrant,  with  two  Telescopes,  reading  to  30 

seconds,  long  centre,  and  seven  shades  in  box     . 

1320  Metal  Quadrant,  best  quality,  divided  on  Ivory,  with 

Achromatic  Telescopes,  long  centre,  seven  shades  and 
index  magnifier,  in  mahogany  box  (fig.  1320) 

1321  Metal  Quadrant,  or  Half  Sextant,  best  quality,  divided 

on  Silver,  with  Two  Telescopes,  long  centre,  seven 
shades  and  index  magnifier,  in  mahogany  box    . 

1322  Ditto,  ditto,  with  extended  Arc 

£      s.     (I 

2  10    0 


3  10    0 


4  10    0 


6  10    0 



FIG.  1322. 

FIG.  1324. 


1322  Black  Glass  Plane,  or  Artificial  Horizon,  with  three 

Levelling  Screws,  and  Ground  Spirit  Level  in  box 
(fig.  1322) 

1323  Artificial  or  Roof  Horizon,  with  Wood  Mercury  bottle 

and  Trough 

1324  Artificial  Horizon,  Ordnance  Pattern,  with  two  Troughs, 

turned  Iron  Mercury  Bottle,  complete  in  mahogany 
box  (fig.  1324) 


£    s.  a. 

2  10  0 

3  10  0 

4  10  0 

1325  Sun  Dials,  circular,  best  Brass, 
full  divided  to  5  minutes,  with 
Equation  Table,  and  hand- 
somely engraved  (fig.  1325) : — 

"Diameter        10-in.         12-in.        14-in.       18-in. 

Price  84s.      115s.    160s.     263s 

FIG.  1325. 

45,    CORNHILL,    B.C.,    AND    122,    EEGENT    STREET,   W.,    LONDON. 




Vertical  Sun  Dial  of 
Stout  Slate  Figures 
and  Divisions  en- 
graved and  Gilt. 
Gilt  Iron  Rod 
Gnomon,  from 

£10  10     0 

Ditto  ditto,  of  Slate 

as  above,  but  with 

Stout      Gun-metal 

Gnomon  (fig.  1327) 

£14  10    0 

Designs  and  Drawings 
of  Vertical  Sun  Dials  fur- 
nished to  Architects  or 
Builders,  with  estimate  of 

FIG.  1327. 

Gnomons  of  any  description,  for  Vertical  Sun 
Dials,  supplied  to  order. 

N.B.  When  ordering  Sun  Dials  full  particulars 
should  be  given  of  size  and  form  'of  Dial  desired, 
and  also  the  Latitude  and  Locality  where  to  be 
fixed  up. 

Skilled  workmen  sent  to  take  Bearings  or  fix 
any  description  of  Sun  Dials. 


1328     Pedestal  of  Terra  Gotta   (fig.   1328)  Height 
3-ft.  6-in.,  suited  for  a  Dial  12  to  14  inches  diameter 


Ditto,  ditto  of  Bath  Stone    .        .        7  12    6 
Estimates  given  for  Pedestals  of  any  design  or 

FIG.  1328. 

1329  Globe  Sun  Dial  or  A  rmillary  sphere,  24-inch 
diameter,  Gilt  Metal  hoops,  with  hour  circle,  on  the 
inside  of  this  are  painted  the  hours  and  divisions, 
the  figures  being  outlined  with  gold,  nickel-plated 
rod  and  terminals.  The  whole  mounted  on  a  solid 
painted  Iron  stand  ....  from  £25  0  0 



FIG.  1330.  FIG.  1332.  FIG.  1331. 

1330  Sun  Dials,  with  Circular  Brass  slab  and  style  (fig.  1330)  :— 

Diameter  .  .  6-in.  8-in.  10-in.  12-in.  14-in. 

Price       .         .          42s.          52s.          63s.          100s.          120s. 

1331  Sun  Dials  on  Slate,  the  style  of  Brass,  12  inclies  Square 

(fig.  1331) £330 

1332  Sun  Dial,  with  burning  lens  so  arranged  that  the  Sun's  rays  are  thrown  on 

the  priming  of  a  small  loaded  Cannon,  and  cause  it  to  be  fired  at  noon 

precisely.     The  mounting  of  the  lens  has  a  scale  corresponding  to  the 

sun's  decimation  for  every  week  in  the  year  (fig.  1332)  £3  12     6      4  10    0 

These  dials  are  constructed  for  the  latitude  of  London.     If  required  for  other 

localities  they  must  be  made  specially  to  order,  and  will  be  slightly  increased  in 



FIG.  1334. 

FIG.  1335. 







FIG.  1340*. 

Pocket  Compasses,  Plain  Needle,  in  square  mahogany 

cases,  with  stops  ....          3s.  6d.    4s.  6d. 
Ditto  ditto,  mounted  with  best  Bar  Needles  and  Agate 

centres  (fig.  1334)          ...          6s.  6d.     7s.  6d.    0  10    6        0  12    6 
Ditto     ditto,      mounted     with    Floating    Card    and 

Agate  centres  (fig.  1335)      .        .          6s.  6d.     7s.  6d. 
Small  Pocket  Compasses,  Round  metal  cases  .        2s. 

0  10 
0    2 

0  12 
0    3 

45,   COBNHILL,    E.G.,   AND    122,   REGENT   STEEET,   W.,    LONDON.  315 

FIG.  1337*. 

1337  Pocket  Compasses,  in  Circular  Brass  boxes  with  covers, 

Magnetic    Needles,   or  Floating  Cards,  with  stops 

(figs.  1337  and  1337*)   6s.  6d.,  7s.6  d.,    0  10    6        0  12    6 

1338  Ditto    ditto,    with    Agate    centre,    and    Bar  Needle 

12s.  6d.    0  15    0        110 

FIG.  1340.  FIG.  1341. 

GEOLOGICAL  AND  SIGHT  COMPASSES.    See  also  page  300. 

FIG.  1342. 

FIG.  1343. 



FIG.  1339. 

FIG.  1344. 

FIG.  1363. 

FIG.  1344. 

1339  Brass  Gilt  Pocket  Compasses,  in  leather  cases,  Plain       £    s.    <M   £    s.    a. 

Needle,  or  Floating  Card  (fig.  1339)  6s.  8s.  6d,  10s.  6d.     0  12    6     0  15     0 

1340  Pocket  Compasses,  with  Enamelled  dials,  in  Gilt  Metal  or  Nickeled  cases, 

Bar  Needles,  or  Floating  Cards,  with  Agate  centres  and  stops,  in  leather 

cases  (figs.  1340  and  1341)    .        .        .     15s.,  18s.  6d.     1    1    0        1  10    0 

These  Pocket  Compasses  are  recommended  for  use  in  Tropical  Climates.     The 

Dials  being  Enamelled  similar  to  a  watch-face,  remain  clean  and  readable,  where 

silvered  metal  or  card  would  become  tarnished  or  obliterated. 

1340*  Patent  Universal  Compass,  Gilt  Metal  Case  with  Pendant  Ring      1  10    0 

1341  Singer's  Patent  Compasses,  with  floating  Pearl  or  Enamelled  Card  Dials, 

One-half  of  the  compass  card  being  Black,  the  points  are  ascertained 
with  ease  at  night  in  the  open  air.  Pocket  sizes  in  various  mountings* 
(figs,  1340, 1344)  10s.  6d.,  12s.  6d.,  16s.  6d.,  £1  Is.  1  10  0  1  15  0 

1342  Geological  Compass,  for  ascertaining  the  dip  or  inclination  of  strata,  hills, 

&c.,  Best  Bar  Needle  with  Clinometer  Scale  (fig.  1342),  showing  the 
inclination  in  degrees  and  inches  per  yard,  in  Round  Brass  box,  4^  inches, 

1  15    0        220 

1343  Pocket  Compass,  plain,  folding,  with  Sights,  round  brass 

box,  Bar  Needle,  and  stop  (fig.  1343)  see  also  page  330  1    1    0        1  10    0 

1344  Watch   Compasses,  in   Bronzed  Metal  Hunting  Case 

(figs.  1334  and  1344*) 21s.    150        1  10    0 

45,    CORNHILL,    E.G.,    AND   122,    REGENT   STREET,    W.,    LONDON". 


1345  Starlight  or  Moonlight  Compasses,  with  transparent  glass  dial  and  bar 
needle,  for  the  use  of  travellers  by  night,  or  by  the  light  of  a  match  or 
cigar,  held  beneath  it,  in  leather  case £330 

FIG.  A. 

FIG.  E. 

FIG.  F. 

FIG.  B. 

1345*  Magnetic  Trinket  or  Charm  Compasses,  mounted  in  Gold  and  Silver  in  great 
variety  of  forms,  as  shown  in  figs.  A  to  F  including  the  new  Transparent  Pebble 
Mountings  (figs.  F  and  B  ),  the  Needle  being  poised  between  the  two  Pebbles. 
These  Pebbles  are  so  worked  upon  their  surfaces  as  to  form  a  Magnifying  Lens 
or  Burning  Glass.  These  Prices  vary  with  the  quality  of  the  G-old  or  Silver  and  the 
design  of  the  frame.  Fig.  A  60s. ;  fig.  B  70s. ;  fig.  E  70s. ;  fig.  F  29s. 

1346  Oat  Beard  Hygrometer,  or  Pocket  Damp 
Detector,  Strongly  gilt  in  morocco  case 
(fig.  1346)  .  .  .  0  10  6  110 

FIG.  1346. 




FIG.  1359. 

FIG.  1350. 

Universal  Jomt  Sun  Dial  and  Compass,  with  divided  Arc,  £  s.    a. 

in  cases 2i-inches  330 

Ditto  ditto .  3^-inches  440 

Ditto  ditto 4^ -inches  660 

Universal  Sun  Dial  and  Compass,  for  both  N.  and  S.  Latitudes,  2£  inches, 

with  Levels  and  Adjusting  Screws,  in  leather  case  (fig.  1350)  440 

Ditto  ditto,  4^-inches,  best  mounting  and  dividing  770 

Watch  Compasses,  in  Silver  Hunting  Cases  .  .  2  10  0  330 

Ditto  ditto  ....  German  Silver,  25s.  1  10  0  2  2  0 



FIG.  1356. 

FIG.  1357, 






FIG.  1355. 

£     s.     d. 

Pocket  Sun  Dial  Compassses,  in  oblong  Boxwood  case, 
with  Equation  Table 

Ditto  with  best  Bar  Needle  ditto  (fig.  1355)    , 

Sun  Dial  Compasses,  in  common  round  wood  case  (fig.  1356) 

Ditto  ditto,  best  Mounted 

Ditto  ditto,  in  Square  "Wood  case,  Agate  Centre,  best 

mounting  (fig.  1357) 0  12  6 

Ditto  ditto,  Round  Metal  Case,  with  cover  and  stop     . 

Ditto  ditto,  German  silver  Nickel  Plated  as  (fig.  1359) 

s.    a- 

0  11 
0  12 
0  2 
0  11 

0  15 
0  12 
0  16 

Starlight  or  Moonlight  Compasses,  with  transparent  glass  dial,  and  bar  needle, 
for  the  use  of  travellers  by  night,  or  by  the  light  of  a  match  or  cigar,  held 


110        1  15    0 

beneath  it,  in  leather  case 

Gregory's  Compass  for  Equestrians,  the  Needle  or  Card 

being  mounted  on  two  centres  to  prevent  oscillation, 

plain  mount  ......... 

Ditto    ditto,   best  mounted  in   Silver   Hunting  case, 

watch  form  as  fig.  1344        ...... 

Symons'   Patent   True   North   Compass,  in   Square 

Mahogany  Box,  with  Agate  Cap  and  Stop  (fig.  1363)     0  10 
Ditto  Ditto,      Trinket   or   Charm  Form, 

Gold  £2  10s. ;  Silver,  £1  2s. 


3  10    6 

0  12     6 

The  true  Magnetic  Westerly  Variation  of  the  Compass  (November,  1885)  for 
London  is  18°  20'  at  Kew,  18°  Greenwich.  The  Annual  decrease,  8'  The  daily 
Oscillation  10'. 

Maximum  Easterly  Variation  yet  recorded  was  observed  by  Burroughs  in 
1580,  viz.,  11°  17'. 

Maximum  Westerly  Variation  observed  by  Colonel  Beaufoy  in  1815,  24°  27'  18". 

Years  of  no  Variation,  1657  to  1662. 

"  As  regards  the  Direction  of  the  Wind,  it  is  hardly  necessary  to  observe  that 
this  should  always  be  given  according  to  True  and  NOT  to  Compass  Searings.  The 
amount  of  Variation  of  the  Compass  in  the  British  Islands  being,  roughly  speak- 
ing, two  points  to  the  westward." 


45,   COENHILL,    E.G.,   AND    122,   BEGENT   STREET,   W.,   LONDON. 



1363  Boat  Steering  Compass,  Plain  mounted,  5-incli,  in  Square   £   s.   d.        £    s.    d. 

Oak  box  with  slide  lid 0  13     0        0  16     6 

1364  Brass  Cone  Boat  Compass,  in  turned  Wood  Case  (fig.  1364)  0  14    0 

FIG.  1364. 

FIG.  1368. 

FIG.  1365. 

1365    Boat  Compass,  Round  Brass  Box, 'in  Gymbals  (fig.  1365)  150       1  12    0 

1367  Ditto  ditto,  Square  Oak  Box,  with  gymbals   ...  1  10     0 

1368  Ditto  ditto,                                Best  Mounted  (fig.  1368)  1  16    0        220 

1369  Ditto  ditto,  Polished  Mahogany  hinged  box  with  Singer's 

Card  (fig.  1369) 220 

FIG.  1369. 

FIG.  1370. 

1370    Improved  Yacht  or  Boat  Compass,  with  Singer's  Patent  or  Ordinary  Card, 
with  or  without  Binnacle  or  Lamps  (figs.  1369  and  1370). 

Size  Of  Compass  Bo,.       Diameter  ot  Card. 

No.  1—4%  inches  square  2^  inches 

No.  2—5^  inches  square  3        „ 

No.  3—  6i  inches  square  3J      „ 


£  a.    d. 
0  14    0 
0  18    0 

£  s.  d. 
1  14  0 

£  s.    d. 

2  16    0 

3  10    0 









FIG.  1372. 

FIG.  1376. 



Ship's  Steering  Compasses,  in  Wood  box : — 

Inches  7.         8.          9.         10.          11. 

Price,  each          8s.        9s.       10s.       11s.        12s! 
Ship's  Steering  Compasses,  best  make,  Agate  Cap  to  Needle,  with 

Brass  bowls  in  gymbals,  and  oak  box  (fig.  1372)  : — 
Size  of  Box  outside,  Inches     7.  8.  9.  10. 

Price,  each  14s.         15s.      17s.  6d.      20s. 

Storm  Compasses,  10-inch 

Ditto     ditto        11-inch 

Storm  Compasses,  double  dipping  Needles,  best  mounted, 

10-inch,  Transparent  Storm  Card         .... 

Ditto      ditto  „  11 -inch  (fig.  1376)     . 

Sox  Ships'  Compasses  are  measured  by  the  outside  of  Box. 

Amplitude  Compass,  brass  caps,  and  steel  centres,  with 
Sights,  Agate,  centre  11 -inch 

Ditto        ditto  10-inch         .... 

Ditto  ditto,  divided  Silver  Ring  and  Folding  Sights  in 

Polished  Mahogany  Box  (fig.  1379)  .  .  .  .410 




£1  10 
1  14 

2  10 
2  15 



5  10    6 





FIG.  1381. 

FIG.  1382. 

Hanging  or  Cabin  Compass,  small  size,  best  mounted, 
japanned  Brass  ........ 

Ditto  ditto,  full  size  ditto,  ditto,  bright  Brass  (fig.  1381) 

Ditto  ditto,  Brass,  turned  arms,  and  best  Transparent 
card  (fig.  1382)  .......  42s. 

Ditto  ditto,  Brass  ditto,  with  Double  Dipping  Needles 

2  10 

1  10 

2  12 

3  0 
3  10 

45,   CORNHILL,    E.G.,   AND    122,    BEGENT   STEEET,   W.,    LONDON. 


FIG.  1384. 



ial  (5 

FIG.  1385. 

i  Sights 






s.     d. 

6    0 

8    0 
2    0 

Prismatic  Azimuth  Compass,  with  Card  Dial  &  Sights 
Best    do.     do.    with  divided  Metal  I 

arranged  for  Iron  Ships  (fig.  1385) 

1385*  Tripod  Stands  for  above 

1386    Prismatic  Azimuth   Compass,   with   double  Needles,   Copper  ring,  inside 

bowl    (Sxow  HARRIS'S  arrangement),   best  mounted   in  mahogany  box, 

specially  suited  for  Iron  ships,  with  extra  Box  for  Card  and  Iron  feeders  to 

preserve  the  magnetism .800 


FIG.  1387*. 

1387  The  principle  on  which  the  RITCHIE'S  LIQUID  COMPASS  is  constructed,  is  the 
enclosing  of  the  magnetic  needles  in  metallic  cylinders,  and  connecting  with  the 
needles  and  the  card  a  closed  air-chamber,  by  the  buoyancy  of  which,  in  the  liquid 
the  bowl  is  filled  with,  the  weight  resting  upon  the  pivot  is  reduced  to  less 
than  a  single  gramme,  preventing  all  friction  and  wear  at  the  point  of  the  pivot. 
The  resistance  of  the  liquid  gives  to  the  card  far  greater  steadiness  than  can  be 

Cabin  and  Transparent  Compasses  are  measured  ly  the  bowl. 



possible  in  any  other  compass,  and  the  card,  if  disturbed,  returns  to  rest  in  much 
less  time.  The  card  is  usually  made  with  a  curved  ring  bearing  the  divisions, 
which  is  preferable,  except  when  it  is  desired  to  be  graduated  to  degrees.  The 
card  with  degrees  is  engraved  upon  a  plane  annular  ring ;  for  use  when  the  courses 
are  desired  to  be  given  in  degrees  rather  than  by  points,  and  which  is  necessary 
for  azimuth  observations.  It  has  EKECT  figures,  which  are  very  legible. 

oS&X    cgj- 


1387*  7 -inch  Compass ;  diameter  of  card  6f -inch,  of  gimbal    £    B.    <a. 
ring  outside  9|-inch,  mahogany  box  11-inch  square, 

Price    450 

8 -inch   Compass ;    Diameter  of   card  7^-inch,  of  ring 
outside    lOf-inch,    mahogany    box    12-inch    square 

(fig.  1387*) .        .        .500 

9-inch   Compass;    Diameter  of  card  8|-inch,  of  ring 

outside  12^-inch,  mahogany  box  13f -inch  square        .600 
10 -inch        ditto        ditto,  diameter  of  card  9|-inch 

£     s.     d. 

4  10    0 


6  10    0 

All  Compasses,  with  graduated  card,  are  arranged  for  use  with  Azimuth  Circle. 
Azimuth  Circles  for  above,  7-inch  to  9-inch   .        .  each  400 

Ditto        10-inch 4  10    0 

Prices  for  any  size-Compasses,  or  specially  fitted  up  to  the  requirements  of  any  Government,  sent  upon  application. 

1388    5-in.   Boats'  Compass,   mounted 

with   Ritchie's    Patent    Liquid 

Compasses,  in  box       .300 

5-in.  ditto  ditto  in  Binnacle  with 

Lamp  (fig.  1388)  .        .    5  10    0 

6 -in.  ditto  ditto  in  box  .440 

6 -in.  ditto  ditto,  Binnacle  770 

7-in.  Pole  Compass,  complete  with 

Support        .        .        .     6  10    0 

8-in.    ditto     ditto        .    7  10    0 

9 -in.    ditto     ditto        .    8  10    0 

7-in.    Transparent    ditto,   [with 

Arms    .  660 

FlG.  1388. 

Binnacle,  Cabin,  or  Saloon,  Engine  room,  Boiler,  and  Forecastle  Lamps.  Hand, 
Gimbal,  or  Hanging  Lanterns,  &c.,  &c.,  of  every  form.  Supplied  to  order. 

Green  and  Ruby  Glasses,  Lenses,  and  Prisms,  Reflectors,  Fittings  for  Ships 
Lamps,  &c.,  &c.  Deck  Glasses,  Flat,  Prismatic,  or  Round,  Glass  Deck  Lights, 
Round  and  Square  Glasses  for  Scuttles,  at  per  Ib. 

Harbour  and  Pier  Head  Lights.  Prices  according  to  size,  colour,  and  power 
of  the  light.  Supplied  to  order. 

45,    CORNHILL,    B.C.,   AND    122,    REGENT   STREET,    W.,    LONDON. 


FlG.  1389. 


No.  1  size  for  Vessels  up  to  300  Tons.    No.  2  size  above  300  Tons  to  536  Tons. 
No.  3  size  600  Tons  to  largest  Vessels  built. 

£     a.     d. 

1389    Port      and      Starboard      Lamps, 

Japanned      .        .        .    per  pair  1  12    6 

Ditto  ditto,  Copper,  (fig.  1389)         .  2  15    0 
Ditto  ditto,  best  quah'ty,  Japanned 

per  pair  200 

Ditto  ditto,  best  Copper  „  400 

Globular  Anchor,  Japanned,  best 

each  0  13    0 

Ditto  ditto,  Copper        .        .    „  140 
Circular  Anchor,   Japanned,   best 

each  0  18    6 

Ditto  ditto,  Copper  .   „  200 

Mast  Head  Lamps,  Japanned,  best 

each  1  10    0 

Ditto  ditto,  Copper        .        .    „  1  10    0 
Tricolour,  Telegraph,  or  Steering 

Lamp,  Japanned  .       .     each  1  10    6 

Ditto  ditto,  Copper  .  „  2  10    0 

£     s.    d. 


2  10    0 

2  12    0 

2  10    0 

3  10    6 

2  18    0 

£     s.     d. 

2  15    0 



1  10    0 

4  12    6 

2  12    0 

3  10    0 

In  our  Appendix  will  be  found  instructions  for  truly  fixing  or  setting  Sun 
Dials ;  also  Tables  of  the  Equation  of  Time,  the  Difference  of  Time  between  various 
localities  East  and  West  of  Greenwich.  The  Height  in  feet  of  the  rise  of  Spring 
Tides  in  various  parts  of  the  world,  &c.,  &c. 



FIG.  A  4. 

FIG.  A 1, 

FIG.  A  2. 

FIG.  A  3. 

1390  Walker's  Patent  Harpoon  Ship-Log  (fig.  A  1.)     . 

1391  Ditto  ditto  (fig.  A  2.)      ....... 

1392  Ditto  ditto,  Detached  Ship-Log  (fig.  A3.). 

1393  Ditto  Harpoon  Sounding  Machine  (fig.  A  4)  without  Lead 
1393*  Lead  for  Sounding  Machine 

£     8.     d. 

3  10  0 

FIG.  A  5. 


FIG  A  6. 

FIG   A  7. 

1394  Massey's  Patent  Ship-Log  (fig.  A  5.)     . 

1395  Ditto,  Improved  ditto,  ditto  (fig.  A  6.)    . 

1396  Massey's  Sounding  Machine  (fig.  A  7.),  with  Lead 

3  10  0 
2  15  0 

45,   COENHILL,   E.G.,  AND   122,   REGENT  STEEET,   W.,   LONDON.  325 

FIG.  1397. 

1397  Walker's  Cherub  Taffrail  Log  (fig.  1397) 

1398  Iron  Governor  Wheel,  for  use  with  above 

1399  Log  Line  for  ditto  ....'. 

1400  Bliss  and  Co.'s  Taffrail  Log,  complete  with  Line 

1401  The  Pendent  Log  supplied  to  order. 

£      B.       d. 

3  10    0 

0  17  0 


£     8. 

0  15 
0  15 

1402  Log  Glasses,  in  Wood  frames,  14  seconds,      per  dozen 

1403  Log  Glasses,  28  seconds,  per  dozen 

1404  Ditto  ditto,  14  and  28  seconds,  best  Brass  frames 

1405  One-minute  Glasses,  in  plain  Wood  frames   . 

1406  Three -minute  ditto  ditto 

1407  Five -minute   ditto  ditto 

1408  Quarter-hour  Glasses      ....... 

1409  Half-hour  Glasses 

1410  One -hour  ditto         *....... 

1411  Two -hour  ditto 

1412  Quarter-hour  Glasses,  in  Rosewood  or  Boxwood  frame  . 

1413  Half-hour    ditto  ditto 

1414  One -hour    ditto  ditto 

1415  Quarter-hour  Glasses  in  Brass  frames  .... 

1416  Half-hour  Glasses  ditto 

1417  One -hour    ditto  ditto 

1418  Tea  Brokers'  Sample  Glasses,  plain  Wood  frame  . 

1419  Auctioneers'  One-minute  Glasses,  Wood  Pocket  case   . 

1420  Tune  Glasses,  mounted  in  Ivory  or  Fancy  Wood  frames  and 




£  s,  d. 


0  1  6 

0  12  0 
0  16  0 
0  11  0 
0  16  0 

0  10    6        0  15    6 
for  any  time. 
To  order. 



FIG.  1428. 

FIG.  1422. 

FIG.  1423. 


£    s.    d. 

£      s.    d. 


1421  Yacht  Binnacle  all  Brass,  short  Urn  shape    . 

1422  Ship's  Binnacles((fig.  1422),  all  bright  Brass,  best  make, 

with  two  Lamps,  bolts,  and  plates  for  deck,  &c. 

10-inch  bowl  11-inch  12-inch 

£12 12s.  £13 13s.  £15 15s. 

1423  Ships'tBinnacle  (fig.  1423),  Globe  shape,  Brass  top,  with 

lamps  on  French  polished  Mahogany  Stand,  11-inch    990      10  10    0 

1424  Brass  Binnacle  Tops,  of  Globe,  Light-house  or  Helmet  form, 

with  two  best  Lamps. 

For  a  10-inch  Compass        11-inch        12-inch        13-inch        14-inch 
£5°  £6  £7  £8  £9 

1425  Brass  Binnacle,  Urn  shape,  with  lion's  head  handles,  adapted  for  Yachts  and 

Steamers,  on  octagon  polished  Mahogany  stand,  with  two  lamps  in  shade  for 
a  10-inch  compass         .......  12  12    0 

1426  Brass  Dolphin  Pattern  Binnacles,  and  other  ornamental 

patterns         .  £12 12s.  15  15    0      16  16     0 

1427  Chain  Boxes  for  Binnacles      ....        extra  0  15    0 

1428  Masthead  Binnacles,  with  band  for  Mast    and   one 

Lamp  (fig.  1428.)    (See  also  Pole  Compass,  page  322.)  550 

Note — The  Compasses  are  not  included  in  any  of  the  above  prices. 

Extra  cost  for  Compass  18s.,  38s.,  to  40s.  each. 

1429  Captain  Friend's  Pelorus,  with  German  silver  Dials,  for  testing 

Compasses        .......... 

6  10    0 

Prices  for  Ritchie's  Patent  Liquid  Compasses,  See  page  322. 

45,    CORNHILL,    E.G.,    AND    122,    EEGENT   STREET,    W.,    LONDON. 


Each.  Each. 

£     s.    d.  £     a.    d. 

1430  Speaking  Trumpets,  Japanned 050  0  15    0 

1431  Ditto  ditto,  Brass 8s.  6d.    0  15    0  0  18    6 

1432  Fog  Horn,  Brass 5s.,  6s.    0  12    6  0  14    0 

1433  Ditto  ditto,  Japanned      ....         2s.  6d.,  4s.    0    5    6  076 

1434  Hand  Fog  Bells,  turned  edge  and  crown : — 

5-inch,  9s. ;  6-inch,  12s. ;  7-inch,  21s.  each. 

1435  Key's  Patent  Fog  Signals,  giving  a  louder  and  more 

prolonged  blast  than  the  fog  horn,  with  Brass  horns  to 

screw  on  bellows  .        .        .        .        .        .        .        .     0  14    0  0  16    0 

1436  Ditto  ditto,  Tin  ditto,  fixed  in  ditto        .        •        .        .    0  12    0  0  14    0 

1437  Ships'    Chronometers,    (8    days),    of    the    very   best 

construction 42     0    0 

1438  Marine  Clinometer  in  Round  Metal  Case    ...  3  10    0 

1439  Marine  Inclinometer,  Admiralty  Pattern       ...  660 

1440  Bar  Magnets,  for  correcting  Compasses         .       per  Ib.  019 

1441  Pitchometer,    for    measuring    the  angle     of    Screw- 

Propeller  Blades  or  Bevel  Wheels.    Supplied  to  order. 

Admiralty  and  Official  Charts,  Maps  of  all  parts  of  the  World,  Nautical 
Almanacs,  Admiralty  Sailing  Directions,  Log  Books,  Cargo  Books,  Journals,  and 
other  Nautical  Publications.  To  order. 

Bunting  of  all  widths  and  qualities,  Signal  Flags,  various  Codes,  in  sets 
roped  and  toggled  complete,  in  painted  boxes,  Royal  Standards,  Ensigns,  Union 
Jacks,  and  all  other  English  and  Foreign  Flags.  To  order. 

Ship's  Compasses  and  Barometers  repaired  and  adjusted. 

Ships'  or  Pilot's  Telescopes,    Binocular  Look-out 
Marine  Barometers,  Drawing  Instruments,  &c.,  &c. 

Glasses    or    Horizon  Sweeps, 
See  Sections. 

COMPASS  VARIATIONS.    From  "  MecJianics'  Magazine,''  March  16*7<,  1865. 



Yearly  Rate  of  Change. 




E     .                           7 




E     .          .              11 




True  North        12 




W   .                    13 




W   .                      9 




W   .        .             5 




W  Max.  W          0 




W  .                      4 




W   .                      7 




FIG.  1442. 

FIG.  1443. 

FIG.  1443*. 

FIG.  1444. 

FIG.  1445. 





3-inch    diameter,    in    hinged    case 

Pocket    Globes, 

(fig.  1442)      .        . '  10s-  6d.  to  16s. 

Pedestal    Globes,  mahogany  base,  with  semi- circular  brass  meridian  and 

Quadrant  of  Altitude  (figs.  1443  and  1443*)  :— 

Diameter  9-in.  6-in.  4^-in.  3-in. 

Each        .        21s.  24s.       9s.    10s.  6d.        6s.    7s.        4s.    5s. 
Table  Globes,  black  stained  wood  frames,  with  brass  meridian  and  Quadrant 
of  Altitude  (fig.  1454) 

Diameter  15-in.  12-in.  9-in. 

Per  Pair     .        .        .        .      £6  6s.  £4  4s.          £3  3s. 

Table  Globes,  mahogany  frame,  with  brass  meridian  and  Quadrant  of  Altitude 

(fig.  1445) :- 


Per  Pair  . 


£10  10s. 


£6  18s. 


£4  15s. 


£3  12s. 

FIG.  1446. 

FIG.  1446*. 

FIG.  1447. 

FIG,  1448. 

1446  Globes  mounted  Chair  high,  best  Plain  mounted  pillar  and  claw,  with 

compass  and  Quadrant  of  Altitude  (figs.  1446  and  1446°)  :— 

Diameter  25-in.  20-in.  15-in.  12-in. 

Per  Pair        .        £25  £14  £9  9s.          £6  6s. 

1447  Globes  mounted  Chair  high,  Superior  Carved  and  polished  pillar  and  claw 

frames,  with  Compass,  Quadrant    of  Altitude,  and  double  hour  circles 
(fig.  1447):— 

Diameter  25-in.  20-in.  15-in.  12-in 

Per  Pair    .        £31 10s.  £16  £11  £7 10s. 

1448  Globes  mounted  Chair  high,  on  highly  finished  and  carved  tripod  frames, 

of  polished  Spanish  mahogany,  with  Compasses,  Quadrant  of  Altitude,  and 
double  hour  circle,  with  all  recent  improvements  (fig.  1448) : — 

Diameter  25-in.  20-in.  15-in.  12-in. 

Per  Pair    .        £36 15s.        £18 18s.          £13  £8 10s 

45,  COKNHILL,  B.C.,  AND  122,  KEGENT  STREET,  W.,  LONDON. 


1449  School  Globes,  mounted  to  suspend  from  the  ceiling 

with  Quadrant  of  Altitude  (fig.  1449) 

Diameter  25-in.  20-in.  15-in.  12-in. 

Each    .        £7  7s.       £3 10s.        £2  2s.        £1 5s. 

1450  Globes  mounted  in  rosewood,  walnut-wood,  satin-wood, 

&c.,  at  10  to  20  per  cent,  increase  on  the  above 
prices.  Any  particular  style  of  frame  made  to 

1451  Covers  for  Globes  of  Leather  Cloth  for  high  frames  : — 

For  25-inch  Globe.        20-inch  Globe.        15-inch  Globe.        12-inch  Globe. 

42s.  32s.  22s.  14s. 

1452  Brass  Quadrants  of  Altitude  :— 

For  25-in.  Globe.  20-in.  Globe.  15-in.  Globe.  12-in.  Globe.  9-in.  Globe.  6-in.  Globe. 

lls.  7s.  5s.          4s.  6d.       3s.  6d.      2s.  6d. 

FIG.  1449. 

Old  Globes  repaired  and  re-covered  with  modern  maps,  and  the  brass  mountings 
cleaned  and  re-lacquered,  rendering  them  equal  to  new. 

FIG.  1454. 

s.     d. 


1453  Orrery  Planitarium,  or  Tellurian,  Plain  mounting  to 

move  by  hand,  showing  the  relative  positions  of  the 

planets  and  their  satellites,  &c  ......  880 

1454  Orrery,  exhibiting  the  relative  positions  of    all  the 

principal  planets  and  their  satellites  ;  the  diurnal  and 
annual  motion  of  the  earth  ;  the  moon's  phases  and 
nodes,  &c.  ;  to  move  with  a  train  of  wheel  work  and 
winch  handles  (fig.  1454)  ......  10  10  0  16  16  0 

1455  Complete  Orreries,  representing  the  motions  of  all  the  Planets  and  their 

satellites  ;  the  various  movements  of  the  earth  and  moon  ;  the  Sun  rotating 
on  its  axis,  &c.  ;  arranged  with  very  superior  clock-work  motion,  in  a 
mahogany  and  brass  frame  .  .  to  order,  from  60  0  0 

1456  Diagrams,  illustrating  the  Sciences  of  Astronomy,  Geography,  Geology, 

&C.,  &C.,  for  Class  teaching,  or  suited  to  Lectures,  supplied  to  order. 




FIG.  1486. 



£      s.    d. 

1457  Small  or  Half-Set  of  Drawing  Instruments,  consisting  of  brass 

compasses,  with  pen  and  pencil  points,  boxwood  scale  and  pencil, 

in  pull-off  case         ..........     066 

1458  Ditto  similar  to  No.  1  set,  but  with  extra  dividers   and 

feeder  (fig.  1458)      ..........    086 

1459  Half-Set  of  Instruments,  consisting  of  brass  compasses,  with  pen 

and  pencil  points,  drawing  pen  and  boxwood  scale,  in  polished 
mahogany  case         .        .........     0  10     6 

1460  Ditto  with  extra  bow  pen,   and    bow  pencil,  and   ebony 

parallel  rule  (fig.  1460)    .........    0  16    6 

FIG.  1458.  FIG.  1463.  FIG.  1460. 

1461     Set  of  Instruments,  consisting  of  brass  compasses,  with  pen  and 

1462    Ditto 

pencil  points,  lengthening  bar,  bow  pen  and  bow  pencil,  drawing 
pen,  ebony  parallel  rule  and  'boxwood  protractor,  fitted  in 
mahogany  case 11 

with  extra  dividers 


45,    CORNHILL,    E.G.,   AND    122,    EEGENT   STREET,    W.,   LONDON. 





FIG.  1467. 

Set  of  Instruments,  consisting  of  brass  sector-joint  compasses, 
with  pen  and  pencil  points,  lengthening  bar,  bow  pen  and  pencil, 
jointed  drawing  pen,  ebony  parallel  rule,  and  boxwood  protractor, 
fitted  in  mahogany  case,  with  lock  and  key  (fig.  1463) 

Set  of  German  Silver  Instruments,  consisting  of  compasses  with 
pen  and  pencil  points,  lengthening  bar,  dividers,  bow  pen,  and  bow 
pencil,  plain  drawing  pen,  boxwood  protractor,  sector  and  ebony 
parallel  rule,  fitted  in  mahogany  case,  with  lock  and  key 

Ditto,  similar  to  No.  1464  set,  but  with  knee-joint  compass, 
and  jointed  drawing  pen 

FIG.  1470. 

1466  Set  of  German  Silver  Instruments,  consisting  of  sector- joint  com- 

passes and  hair  dividers  pen  and  pencil  points,  lengthening  bar, 
bow  pen  and  bow  pencil,  jointed  and  plain  drawing  pens,  box- 
wood protractor  and  sector,  and  ebony  parallel  rule,  fitted  in 
oak,  rosewood  or  mahogany  case,  with  lock  and  key  . 

1467  Set   of  German   Silver   Instruments,   consisting   of   knee-joint 

compass,  as  fitted  with  set  of  three  spring  bows  and  plain 
drawing  pen,  fitted  in  oak  or  mahogany  case,  with  lock  and  key 
(fig.  1467)  

1468  Set  of  German  Silver  Instruments,  similar  to  No.  1466  set,  but  with 

extra, set  of  three  best  spring  bows        .        ,        .        .        .        . 


1  10    0 

1  15    0 


2  10    0 


3  10    0 


£    s.     d. 

1469  Set  of  German  Silver  Instruments,  best  finished  sector-joint  com- 

passes and  hair  dividers,  pen  and  pencil  points,  lengthening  bar, 
bow  pen  and  bow  pencil,  set  of  three  best  spring  bows,  jointed 
and  plain  drawing  pens,  needle  holder,  ivory  protractor,  sector 
and  parallel  rule,  fitted  in  oak,  rosewood  or  mahogany  case,  with 
lock  and  key  .  .  .  .• '.  .440 

1470  Set  of  German  Silver  Instruments,  similar  to  Fig.  1470,  but  with 

best  knee-joint  compass,  and  with  brass  bound  case,  with  best 

silk  linings 550 

1471  Set  of  German  Silver  Instruments,  similar  to  No.  1470  set,  but  with 

set  of  colours,  brushes,  &c 5  15     0 

1472  Set   of  German  Silver  Instruments,  consisting  of  best   double  - 

jointed  and  needle-pointed  compasses,  hair  dividers,  pen  and 
pencil  points,  lengthening  bar,  bow  pen  and  bow  pencil,  set  of 
three  best  spring  bows,  jointed  and  plain  drawing  pens,  ivory 
protractor,  sector  and  parallel  rule,  fitted  in  brass  bound  case, 
with  lock  and  key 660 

1473  Set  of  German  Silver  Instruments,  similar  to  No.  1472  set,  but  with 

needle  holder,  and  set  of  best  colours,  brushes,  &c.        .        .        .770 

1474  Set  of  German  Silver  Instruments,  similar  to  Na  1473,  but  fitted  in 

extra  finished  Case,  with  G-erman  Silver  caps  and  corners,  &c., 
suitable  for  presentation  •• 880 

1475  Set  of  German  Silver  Instruments,  similar  to  No.  1474,  but  with 

fully  divided  proportional  compass .990 

FIG.  1474. 

1476    Set  of  German  Silver  Instruments,  similar  to  1475,  but  with  dotting 

and  road  pens  . 10  10    0 

45,   CORNHILL   E.G.,   AND    122   REGENT    STREET,  W.,    LONDON. 


FIG.  1478. 

£     a. 

1478  Addiscombe  Cadets'  Set  of  Drawing  Instruments,  consisting  of 
brass  sector  joint  compasses,  with  pen  and  pencil  points,  length- 
ening bar,  hair  dividers,  bow  pen  and  bow  pencil  jointed  and 
plain  drawing  pens,  ivory  red  line  protractor,  sector  and  parallel 
rule,  boxwood  marquoise  scales  and  angle,  in  oak  case,  with  lock 
and  key 3  10 

1478*  Ditto  ditto  in  German  Silver,  rosewood  case  .  .    4  10 

FIG.  1481. 

1479  Ordnance  Pattern  Set  of  Drawing  Instruments,  consisting  of  brass 

sector  joint  compasses  with  pen  and  pencil  points,  lengthening 
bar,  dividers,  bow  pen  and  bow  pencil,  jointed  and  plain  drawing 
pens,  ivory  protractor  sector,  and  parallel  rules  and  drawing  pins 
in  mahogany  case  with  snap  fastening 2  10  0 

1480  Ditto  ditto  in  German  Silver,  with  hair  dividers    .        .330 

1481  Set  of  Mathematical  Drawing  Instruments,  as  used  at 

the  Royal  Military  College,  Woolwich        ...  330 

1482  Set  of  Mathematical  Drawing  Instruments,  as  used  at 

King's  College  and  College  of  Civil  Engineers         .    2  15    0        3  10    0 


FIG.   1485. 

1484  Pocket  Set  of  Drawing  Instruments,  consisting  of  small  sector  £    s.    d. 

jointed  German  Silver  compasses,  with  pen  and  pencil  points, 
lengthening  bar,  hair  dividers,  jointed  drawing  pen,  and  ivory 
protractor,  fitted  in  Morocco  case 2  10  0 

1485  Pocket  Set,  consisting  of  best  double  jointed  and  needle  pointed 

German  Silver  compasses,  with  pen  and  pencil  points,  lengthening 
bar,  hair  dividers,  bow  pen  and  bow  pencil,  jointed  and  plain 
drawing  pens,  ivory  protractor,  sector,  and  parallel  rule,  fitted  in 
Morocco  case  (fig.  1485) 4  10  0 

1486  Magazine  Cases  of  Mathematical  and  Engineering  Drawing  In- 

struments, of  our  very  best  manuf  acture,  in  German  Silver.  These 
sets  include  proportional  compasses,  beam  compasses,  various 
sizes  of  drawing,  road,  and  wheel  pens,  dividers,  sets  of  the  best 
spring  bows,  bow  pens  and  bow  pencils,  complete  sets  of  architects' 
scales,  plotting  or  chain  scales  and  off-sets,  curves  and  angles, 
plain  and  rolling  parallel  rules,  circular  and  semi -circular  pro- 
tractors, drawing  pins,  set  of  water  colours,  brushes,  palettes, 
saucers,  &c. ;  arranged  in  brass-bound  polished  mahogany, 
oak,  or  rosewood  cabinets,  best  locks  and  keys  with  trays  and 
drawers  (fig.  1486)  ....  £15  15s.;  £22;  £25  and  30  0  0 


Each.  Each. 

£    s.    d.  £    s.    d. 

1487  Dividers,  Brass-jointed,  5  and  6-inch     .  from  per  doz.  0  12    0 

1488  Dividers,  Steel-jointed    ....  each     Is.  6d.    0    2    6  030 

1489  Five  and  Six-inch  best  Brass  Sector-joint  Dividers      .046  050 

1490  Ditto        ditto,  German  Silver        .        .        .(fig.  1490)    050  060 

1500  Five  and  Six-inch  Hair  Dividers,  Brass .       .       .       .070  086 

1501  Ditto       ditto       ditto,  German  Silver         .  (fig.  1501)    086  0  10    6 

1502  Pocket  Dividers,  with  sheath 076  0100 

1503  Double-jointed  Dividers,  with  Needle  Points, 

German  Silver  1  18    0 

45,    CORNHILL,   E.G.,   AND    122,    REGENT   STREET,   W.,   1ONDON.  33o 

FIG.  1523. 

FIG.  1501.  FIG.  1505, 

FIG.  B. 

FIG.   1490. 

1504  Compasses  or  Dividers,  best  brass,  6-inch,  with  pen 

and  pencil  joint,  and  lengthening  bar 

1505  Ditto     ditto     German  silver  best,  (figs.  1490  and  1505) 

1506  Pocket  Turn-in  Dividers,  brass 

1507  Ditto      ditto        ditto,  German  silver  .... 

1508  Spring  Dividers,  all  Steel,  with  Adjusting  screw  . 

1509  Bow  Pens,  or  Bow  Pencils,  Brass 

1510  Ditto        ditto,  best  (fig.  1510)  German  silver 

1511  Ditto       ditto  ....   with  Extra  Joints 

1512  Steel  Spring  Bow  Pens   (fig.   A.)  with  best  Needle 


1513  Ditto    ditto    Pencils  (fig.  B) 

1514  Ditto    ditto    Dividers  (fig.  C) 

1515  Ditto    ditto    best  Swiss        ....          each 

1516  Set  of  Spring  Bow  Dividers,  Pen  and  Pencil,  in  Pocket 


1517  Ditto       ditto,  best,  with  Needle  Points  (fig.  1517)      . 

1518  Double-pointed  Bow  Pen,  with  Turn-over  pen,  pencil; 

and  point,  in  case 

£       8. 














0  10 





0    7 

















0    10    6 

0  16    0 

0  18    0 



FIG.  1548. 

FIG. 1517. 







FIG.  1524.    FIG.  1525.  1533 

Plain  Drawing  Pen,  with  brass 

handle     and    protracting    pin 

Ditto       ditto,       all  Steel 
Drawing  Pens,  with  Ivory  handle    026 
Ditto  ditto,  with  lift  Brass  joints 

to  the  blades,  and  Ivory  handle 
Drawing  Pens,  best  German  Silver 

lift  joints  and  spring  (fig.  1523) 
Drawing  or  Bordering  Pens,  for 

very  thick  lines  (fig.  1524) 
Dotting  Pen,  with  Ivory  handles 

and  Wheels  (fig.  1525)      .        . 
Road  Pen      ..... 
Ditto  ditto  for  Pencil  . 
Needle  Holder,  or  Pricking  Point 
Ditto  ditto,  best  improved  (fig.  1529) 
Map  Meter  or  Opisometer,  for 

measuring  Curved  lines  on  plans 

or  charts  (fig.  1280)  see  page  305. 

2s.  6d.    0 

Triangular  Compasses,  Brass 
Ditto   ditto,   German  silver,  with 

shifting  leg         .... 
Elliptical  Compasses  or  Trammel    2 

£       F.       (1. 



056        066 

0  10    6 


10    0 

0  10    6 

0  16  0 
0  10  6 
0  10  6 


1  10    0 

FIG.  1535.  FIG.  1536. 

1534  Proportional  Compasses,  common  Brass        ...  0  12  6 

1535  Ditto  ditto,  with  Hackwork  Adjustment  (fig.  1535)      .  1  10  0 

1536  Ditto        ditto,    full  divided,  German  Silver  (fig.  1536)  1  12  6 

i-5,  COUNHILL,  E.G.,  A\D  12'?,  EEGENT  STREET,  W.,  LONDON.        337 

FIG.  1538. 

FIG.  1539. 

1537  Proportional    Compasses,    full    divided,    best    make,  &    s.    d. 

Tangent     Screw,     Screw    Adjustment,    in     hinged 
Leather  Case 

1538  Pocket  Divider,  with  turn-in  points  ^fig.  1538)      .        . 

1539  Napier's  Pocket  Compasses,  with  Revolving  pen  and 

pencil  points,  in  neat  hinged  case  (fig.  1539)        .         .110 

1540  Ditto     ditto     Best  Mounted 


076        0  10    6 

1  15    0 

FIG.  1543. 

FIG.  1544. 

1541  Pillar  Compasses,  in  Brass     .       .       .       .       .       .    0  15    0 

1542  Ditto  ditto,  German  Silver,  in  case         .... 

1543  Ditto  ditto,  with  Lengthening  Bars,  in  case  (fig.  1543) 

1544  Ditto  ditto     .         .   with  Ivory  scale,  in  ditto  (fig.  1544") 


The  Pillar  Compasses  form  a  most  convenient  pocket  set  of  Drawing  Instru- 
ments for  travellers,  comprising  a  large  pair  of  dividers,  with  pen  and  pencil  joint, 
also  a  bow  pen  and  bow  pencil.  Nos.  1543  and  1544  have  lengthening  bars,  by  which 
very  large  circles  and  curves  may  be  drawn  either  in  ink  or  pencil. 

1545  Whole  and  Half  Compasses  (fig  1545)    ....  110 

1546  Tube  Beam  Compasses 2  15    0 

1547  Beam  Compass  fittings,  plain,  for  any  bar    .        .        .150        1  10    0 

1548  Best  ditto  ditto,  with  Tangent  Screw  and  Pen  and 

Pencil  points  (fig.  1548)  in  case 250 

1549  Tube  Compasses,  with  case  and  scale    ....  220 

1550  Ditto  ditto        .        .        .    best  Sector-jointed,  in  case  2  12    0 

1551  Callipers,  Proportional,  12-inch 220       2  12    6 

1552  Ditto  ditto        .  9-inch  1  16    0        220 



FIG.  1556. 

FIGS.  1556*  1557   FIG.  1553* 

FIG.  1554. 


1553  Small  sets  of  Drawing  Instruments,  without  boxes. 
1553*  Compasses  with  pen  and  pencil  joint  and  lengthening     £ 

bar  (fig.  1553*) per  set 

1554  Ditto        ditto,  with  drawing  pen  (fig.  1554)        per  set 

1555  Ditto        ditto,  Steel-jointed 

1556  Common  Ruling  pens  (figs.  1556  and  1556°)  .        .  each    016 

1557  Ditto        ditto,  for  Double  lines  (fig.  1557)     . 

Sets  of  French  or  Swiss  Drawing  Instruments,  in 
convenient  flat  mahogany  or  rosewood  hinged  boxes, 
adapted  for  Elementary  School  purposes 

3s.  6d.,  5s.  6d.,  8s.  6d.,  10s.  6d,    1    5    0        1  10    0 

SCALES,   RULES,   &c. 

FIG.  1558. 

1558  Parallel  Rules,  Ebony,  Plain  Brass  Bars :— (fig.  1558) 

6-in.           9-in.           12-in.  15-ia.               18-in.               24-in. 

Is.       Is.  9d.    2s.  6d.  3s.  6d.       4s.  6d.        7s  6d. 

1559  Ditto  ditto,  Ebony,  Brass  Edged— 

6-in.           9-in.           12-in.  15-in.              18-in.              24-in. 

5s.       6s.  6d.      9s.  12s.         14s.  6d.      18s.  6d. 

FIG.  1560. 
1560    Parallel  Rules,  Rolling,  Ebony,  Plain:— (fig.  1560) 

6-in.  9-in.  12-in.  15-in. 

7s.  8s.  10s.  6d.  14s. 



45,    CORNHILL,    E.G.,   AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  1561, 

1561  Rolling  Parallel  Rules,  best,  with  full  diviled  Ivory  or 

Metal  Edges  and  Boilers :— (fig.  1561) 

6-in.  9-in.  12-in.  15-in.  18-in. 

13s.          16s.  6d.         21s.  25s.  30s. 

1562  Parallel  Rules,  Rolling  Brass,  best :—  : 

6-in.  12-in.  18-in.  24-ir. 

12s.  6d.  25s.  38s.  50s. 

1563  Ditto  ditto,  German  Silver  : — 

6-in.  12-in.  18-in.  24-in. 

18s.  36s.  55s.  72s. 

1564  Mahogany  Case  for  ditto  : — 

6-in.  12-in.  18-in.  24-in. 

4s.  6d.  6s.  8s.  10s. 

1565  Architects'  Scales,  12-inch  Boxwood      .... 

1566  Ditto       ditto        12-inch  Boxwood,  fully  divided 

1567  Ivory  Architects'  Scales,  12-inch  (fig.  1567)   . 

1568  Ditto  ditto  6 -inch      .  .... 

1569  Ivory  Architects'  Scales,  12-inch  best,  fully  divided,  from 

^  to  3  inches,  containing  16  scales     .... 

£    s.    d. 

FIG.  1567. 

1570  Six-inch    ditto  ditto 

1571  Chain  or  Plotting  Scales,  Best  Ivory,  12-inch  80  to  100 

1572  Off-sets  for  ditto        .        Best  Ivory,  2-inch 

1573  Chain  or  Plotting  Scales,  best  Ivory,  12-inch,  10  to  60 

chains  to  the  inch        .         . 

1574  Six-inch  ditto  ditto,  best  Ivory  . 

1575  Off-set  Scales,  Ivory,  10  to  60         .       .       .        from 

1576  Chain    or  Plotting  Scales,   best  Boxwood,    12-inch, 

10  to  60 . 

1577  Ditto  ditto,  12-inch  Best  Boxwood,  ditto  80  to  100 

1578  Ditto  ditto,  6-inch  Boxwood    ditto        .... 

1579  Off-sets,  Boxwood,  10  to  60 

1580  Off-sets,  Boxwood,  80  to  100 

1581  Complete  sets  of  best  Ivory  Plotting  Scales  and  Off-sets, 

12-inch,    from    10    to   100   chains  to  the  inch,   in 
mahogany  case,  with  lock  and  key 

1582  Complete  sets  of  best  Boxwood  Plotting  Scales,  12-inch 

with  off-sets,  10  to  100  chains,  in  Mahogany  box 

1583  Set  of  Six  ditto        ...... 

1584  Six-inch  Ivory  Parallel  Rules,  German  Silver  Mounts  . 

£    a.    d. 

0  12  6 

0  16    6 

'.  |^L  urn  JIM  M|  IN  i'^"2ui|^j 

LM  I  1  I  1111  J 

'  1  1  "  1 

riri  MI  u  j  ii 

[in  i  LI 

1  1  1  1  1 




5  fe.  *r  «L  a 




0  10  6 
0  15  0 

0  10  6 


0  5 

i  2 


1  10  0 



Each.  Each. 

£    s.      d.  £    s.    d. 

1585  Six-Inch  Ivory  Sector  Scales  .  .060080 

1586  Six-inch  Ivory  Protractors      .       ..''-.       •       •       .050  06o 

1587  Ditto              best  full  divided  Ivory  ditto      ...  086 

1588  Twelve-inch  Ivory  Protractors,  full  divided  ...  160 

1589  Red-line  Protractor,  best  for  Military  Drawing     .  066 

1590  Ditto  ditto,  Ivory      .        .        .    best  with  scale  of  feet  0  10    0 , 

1591  Six-inch  Boxwood  ditto  Sectors      .  026 

1592  Six-inch  Boxwood  Protractors 010  026 

1593  Six-inch  Ivory  best  Navigation  Scales,  full  divided      .  0  10    6 
!594    Six- inch  Military  best  Ivory  Scales        ....  0  10    6 

1595  One-foot  Gunter's  Scales,  Boxwood        ....  030 

1596  Two-feet  ditto  ditto 050 

1597  Two-feet  Sliding  Gunter's  Scales,  (Bonn's)    ...  0  10    6 

1598  Marquois  Scales,  Boxwood,  in  case  complete  0  10    6 

1599  Ditto      ditto,      without  case 086 

1600  Ditto      ditto      Ivory 3  10    0 

1601  Ditto      ditto      Metal 440 

1602  Gunner's  Rules       ,..'..-•  0  10    6 

1603  Negretti   and   Zambra's   2-foot  4-fold  Ivory   Pocket 

Rule,  combining  the  Protractor,  Sector,  and  a  2-foot 

rule,  best,  full  divided,  in  leather  case          ...  3  10     0 

FIG.  1611. 

1604  Protractors,  in  Horn,  semi-circular,  transparent,  very 

convenient  for  roughly  measuring  angles  on  paper, 

Divided  into  degrees— 3-in.        3^-in        4-in.        5-in.        6-in. 
6d.          8d.          lOd.     *  Is.  6d.        2s. 

1605  Card  Protractors,  Ordnance  Pattern       ....  036 

1606  Brass  Protractors,  plain  Semi-Circular  .  .       .076       0  10    6 

1607  Brass  Semi-  Circular  Protractors,  plain  divided  to  ^  degs. 

or  30  minutes        . 110        1  10    0 

1608  Brass  Semi-Circular  Protractors,  6-inch,  with  Arm  and 

Yemier,    transparent  centre    (see     fig.   1241,  page 

303),  in  Box 330 

45,  COENHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON. 

1609  Brass  Circular  Protractors,  plain—  6-in          8-'n.  10-in. 

25s.  32s.  42s. 

1610  Circular  Protractors,  Brass,  6-incli,  (fig.  1610)  with.  Tangent  screw 

adjustment  and  clamp  to  Yernier,  in  mahogany  box  . 

1611  Ditto        ditto        best  6-inch,  divided  on  Silver,  with 

Folding  Arms  (fig.  1611) . 

1612  Ditto        ditto        7-in 

16]  3    Ditto        ditto        8-in. 

FIG.  1615. 

1614  Station  Pointers  for  Hydrographical  Surveys,  6-inch 

plain,  divided  on  Brass,  with  12-inch  arms 

1615  Best     ditto     6 -inch,   with  Silver  divided  Circles  and 

Yerniers,  Tangent  Screw  adjustments  (as  fig.  1615), 
with  arms  lengthening  to  18  inches,  in  mahogany  case 
7-inch  ditto     ditto,  arms  lengthening  to  24  inches 
8-inch  ditto    ditto  to  30  inches 


£     s.     d. 


4  15    0 

7  15    0 

11  0  0 
13  0  0 
15  15  0 

FIG.  1618*.    FIG.  1619.  FIG.  1618.  FIG.  1610. 

1618    T  or  Drawing  Squares,  Mahogany,  with  Ebony  Edges  :— 

12-inch  plain  (fig.  1618)  3s.  6d.,  with  bevel  (fig.  1618*)  0    4 

18-inch      „        .        .    4s.                „  0    5    0 

24-inch                        .     6s.                „  060 

36-inch                       ,    4s.  076 



FIG.  1630A.  FIG.  1630s.  FIG.  1630c. 

1618°  T  or  Drawing  Squares,  Mahogany,  with  Ebony  Edges :—  &    B.  a. 

42-inch      „ 0  10  6 

48-inch      „ 0  12  6 

54-inch      „  0  15  0 

1619  T  Squares,  Mahogany,  with  shifting  bevel  and  clamp, 

best  (fig.  1619)  :— 

18-in.  24-in.  36-in.  42 -in. 

5s.  6d.  7s.  6d.  10s.  12s. 

1620  T  Squares,  Ebony,  plain  :— 

18-in.  24-in.  36-in. 

6s.  6d.  8s.  6d.  13s  6d. 

1621  T  Squares,  Ebony,  with  shifting  bevel  and  clamp  :— 

18-in.  24-in.                    36-in. 

8s.  6d.  10s.  6d.               15s.  6d. 

1622  Steel  T  Squares,  per  inch       .  008 
16^3    Steel  Triangles'. •   various 

1624  Steel  Straight-edges,  stout  best,  per  foot      ...  046 

1625  Ditto        ditto        flexible,  per  foot        .  030 

1626  Ditto        ditto        best  London  make,  2  inches  wide,  in 

Pine  Case : — 

42- in.  52-in. 

24s.  £1  12s.  6d. 


FIG.  1627. 

1627     Ivory,  Ebony,  or  Boxwood  Acute,  Obtuse,  and  Right 

Angles,  or  Set  Squares,  various  (fig.  1627),  from  Is.;    026 

1629  Mathematical  Curves  or  Scrolls,  Pear  Tree  Set  of  12  . 

1630  Architectural  Curves,  30  different  forms  (figs.  1630  ABC) 

Is.    0    2    0 

1631  Set  of  Radii  Curves  (fig.  1631)       .       .       .       .       .110 

0    7 
0  12 

45,   CORNHILI,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 









Railway  Curves,  in  Cases : — 

Set  of  25      .... 

Set  of  50      . 

Set  of  100     .... 
Ship  Curves,  in  Cases  :— -(fig.  1633) 

Set  of  15      .... 

Set  of  40      .... 

Set  of  80 

Cardboard  Peartree  Vulcanite 

£0  11     6  £100  £1  15    0 

130  1150  3100 

220  350  5150 

0  12    6 

1  15    0 
3  10    0 

1  10 
3  17 

7  10 


FIG.  1638.  FIG.  1631. 

Ebonite  Scales,  Rules,  Set  Squares,  Curves,  Slopes,  and  Batters  for  Railway 

Embankments,  &c.,  at  a  slight  advance  on  the  price  of  Boxwood. 
Mitfbrd's  Double  Set  Of  Ivory  Pocket  Scales,  arranged  for  Engineers,  Architects, 
&c.  The  length  of  each  scale,  six  inches  ;  the  form  of  a  single  scale,  a  right-angled 
triangle,  two  making  a  square  or  set  ;  the  two  sets  are  packed  in  a  leather  case,  and 
the  ends  of  each  scale  stamped  with  its  value.  The  triangular  form  enables  all  the 
scales  to  be  conveniently  placed  on  the  edges.  The  scales  are  seventeen  in  number 
fully  divided,  viz.,  2,  3,  4,  6,  8,  and  10  chains  to  the  inch  ;  66  feet  and  6  inches  to 
the  mile  ;  T^,  &,  T\j,  £,  £,  £,  f-inch,  and  French  Metre  ;  the  Ordnance  scale  and  a 
line  of  chords  ;  a  number  of  constants  carefully  worked  out,  are  placed  on  the  faces 
of  each  scale. 

Price  for  complete  set,  in  case 

Horn  Centre  Pieces  /.        per  doz. 

Drawing  Pins,  Brass        .        .        .        .       .     „      Is. 
Ditto  ditto,  German  Silver      .        .        .        .    „  Is.  6d. 
Drawing  Pencils,  all  kinds  and  colours.    To  order. 
Small  Pencils  for  Mathematical  Instruments,   per  doz. 

Crayon  Holders from 

Drawing  Boards       .        .    5s.  6d.,  8s.  6d.,  12s.  6d.5  15s. 
Black  Board  Compasses,  Wood  and  Metal    . 
Tracing  Paper          .        .        .        .per  sheet,  3d.,  4d. 

Ditto  Cloth per  yard 

Pen  Machines  for  making  or  mending  Quill  Pens 
Cutting  Compasses  of  Steel,  with  Screw  adjustment 

and  three  knives,  for  cutting  Circles  of  Cardboard  to 

4  inches  diameter          ....... 

Paper  Weights  for  holding  drawings  or  papers  flat  on 

a  table.     Circular 

Ditto  ditto,  Oblong,  leather  covered  .... 
Brass  Clamps  to  fasten  Straight-edge  to  drawing  board 
Erasing  and  Pen  Knives  .  ...  Is.  6d. 
Lamps  with  Shades  for  Drawing  Table  or  Board,  either 

for  Gas,  Oil,  or  Paraffin 


0  10 
0    0 












0  12    6        0  15    0 




2  10    0 

Engraving  name  on  Case  of  Drawing  Instruments  with  date,  2s.  6d.  to  5s. ;  Crests 

or  Monograms,  5s.  to  10s.  6d. ;  Presentation  Inscriptions  varying  according 

to  the  Length  and  Style  of  engraving,  ornamentation,  &c. 



FIG.  1(558. 

1653  Mahogany  Slide'.Lid  Boxes,  Half  Cakes         .       5s.  6d. 

1654  Ditto        ditto        Whole  Cakes      .         .        .        . 

1655  Twelve-cake  Water  Colour  Box,  mahogany,  with  lock 

and  key         . 

1656  Twelve -cake      ditto     ditto,     with   drawer    containing 

saucers,  brushes,  pencils,  &c 

1657  Eighteen-Cake  Water  Colour  Box,  caddy  lid,  mahogany, 

with  drawer  containinggink stone,  palettes,  cut  water 
glass,  extra  brushes,  pencils,  &c.  .... 

1658  Twenty-four  and  Thirty- Cake  ditto  ditto,  handsome 

Spanish  mahogany,  brass  clamped,  and  with  superior 
fittings,  (fig.  1658) 

1659  Thirty-Cake  Water  gColour  Box,  with  a  complete  set  of 

German  Silver  Drawing  Instruments,  Ivory  Rules 
and  Scales,  Rosewood  or  Oak.  German  Silver  bound, 
very  handsome,  Suitable  for  Presentation  . 

£  s. 
0  7 
0  10 



£     s. 

0  10 
0  15 


1    5 

1  10    0        220 

440        550 

15  15    0 

1660  Moist  Water  Colours  in  Japanned 
Tin  Box,   with    selected    list  of  Im- 
proved Moist  Colours  for  Photographic 
Portraiture,  &c.,  Best  Sable  and  Camel 
Hair  Brushes.  &c.  (as  fig.  1660) 

£1  Is. ;  £1  10s. ;  £2  2s. 

Any  special  Colours  supplied  to  order. 

1661  Lock  Mahogany  Box,  with  velvet 
Palette,  Brushes,  Stumps,  Shells,  &c.. 
with     24    Colours  for    colouring    or 
Tinting  Photographs,     £2  2s. 

FIG.  1660. 

45,    CORtfHILL,   E.G.,   AND    122,    EEGENT   STREET,   W.,    LONDON.  845 


1662  Gauging  Instruments,  as  used  by  the  Board  of  Customs,  a  Complete  Set, 

consisting  of  Long  Calliper,  Cross  Calliper,  Bung  Rod,  with  brass  slider, 
4-feet,  and  Head  Rod,  with  book  of  instructions  for  use,  adapted  for 
Spirit  or  Oil-gauging  .  . Price,  £440 

1663  Gauging    Rods,   straight,   with  line   of  inches  and  tenths,   diagonal  line. 

Dips  for  every  sized  spirit  and  beer  casks. 

Lancewood.  4ft.  5ft.  6ft. 

6s.  6d.  8s.  6d.  9s.  6d. 

1664  Dipping  Wine  and  Spirit  Rules,  with  similar  scales  and  divisions 

as  above.  s.    d.  s.    d. 

3  feet,  4  fold    ...        6    6 

3  „     6    „      .        .        .        86 

4  „     4    „  76 

5  feet,  8  fold  .  .  .  12  0 

6  „     6    „  .  .  .  12  0 
6    „     8    „  .  .  .  14  0 
6      ,    12  22  0 

4  „     6    „      .        .        .        96 

5  „     6    „      .        .        .      10    6   ( 

1665  Double  Diagonal  Rods,  Imperial  and  Old  measure,  with 

table  of  Outs  of  Casks. 

1666  Double  Diagonal  5-feet  Gauging  Rod,  with  table  .       .  086 

1667  Ditto,        ditto    4  ditto  ditto  .  066 

1668  Spile  Rods,  Boxwood,  screw  jointed.     For  gauging  the 

dip  of  a  cask  through  the  spile  hole. 

6-feet  Spile  Rod,  screw  joints 0  14    6 

5-feet          ditto  ditto 0  12    6 

4-feet          ditto  ditto 0  10    6 

3-feet          ditto  ditto 086 

1669  Spile  Rod,  without  joints 036 

1670  Proof  or  Temperature  Slide  Rules,  6-inch,  boxwood, 

for  use  with  Sykes'  hydrometer 046 

1671  Comparative  or  Reducing  Slide  Rule,  showing  the  number  of  gallons  of 

water  required  to  reduce  spirits  from  a  high  to  a  low  strength,  &c.,  &c., 
as  supplied  with  Sykes'  Hydrometer,  6 -inch,  boxwood  096 

1672  Sliding  Rule,  for  correcting  the  indications  of  the  Hydrometer,  when  the 

temperature  of  the  spirit  is  either  above  or  below  55  degrees  of  Fahrenheit. 
The  rule  is  composed  of  two  parts,  the  long  scale  being  divided  similar  to 
the  Hydrometer,  ranging  from  45  under  to  70  over  proof,  the  small 
moving  scale  representing  temperatures  from  30  to  80  degrees  Fahrenheit. 
This  Rule  is  used  as  follows.  Having  placed  the  Hydrometer  in  the  spirit 
to  be  tested  and  noted,  the  reading  on  the  scale — say,  for  example,  20  over 
.  proof  ^  take  the  temperature — say  it  is  70.  Now  move  the  sliding  scale 
until  the  star  is  directly  opposite  20  O.P.  on  the  long  scale,  and  opposite 
the  70  of  the  temperature  scales  will  be  found  15  over  proof,  which  is  the 
strength  of  the  spirit.  Price,  4s.  6d. 

1673  Ullage  Rules,  Plain,  for  use  with  dip  rod  or  rules. 

12-in.  18-in.  24-in.  36-in. 

7s.  10s.  6d.  14s.  6d.  18s.  6d. 

1674  Gauging,  Ullaging,  Reducing  and  Valuing  Rule,  with 

two  slides       ......... 

In  conjunction  with  a  dip  rod,  this  rule  will  gauge  the 
contents  of  any  cask,  and  give  the  value  of  spirits. 

9-in.  12-in.  18-in.  24-in. 

10s.  6d.  12s.  6d.  14s.  6d.  18s.  6d. 


£    s.     d. 

1675  Book  of  Instructions  for  using  Nos.  1134  and  1234      .  020 

1676  Float  Rod  or  Bung  Gauge,  plain  mounted,  3  to  20  feet. 

3ft.  4ft.  5ft.  10ft. 

7s.  6d.  10s.  6d.  13s.  6d.  26s. 

1677  Ditto  ditto,  100  inches,  with  improved  Joints       .  250 

1678  Oil  Rods,  round  steel,  divided  into  inches,  tenths,  and 

diagonals  3  feet,  25s. ;  6  feet  1  10    0 

1679  Screw  Sticks,  9-inch  joint.    See  Spile  Rods,  No.  1236. 

1680  Malt  Rods  or  Sticks,  round  wood,  divided  into  inches, 

tenths,  and  diagonals. 

30-in.  36-in.  48-in.  60-in. 

5s.  6d.  6s.  6d.  7s.  6d.  8s.  6d. 

1681  Malt  Rods  or  Sticks,  Round  Brass,  per  foot,  6s.  6d. 

1682  Ditto  ditto  flat  ditto  5s.  6d. 

1683  Malt _.  Receivers,  for  sampling  malt  from  a  bin  or  sack, 

4s.  6d.,  7s.  6d.,  and  10s.  6d. 

1684  Malt  House  Steel  Cistern  Rod,  strong  Brass  mountings, 

showing  to  50  inches 0  15    6 

1685  Malt  House  Couch  Rod  .       .  ' 076 

1686  Gauging  Tape  Measure,  or  Malt  Tapes. 

400-in.  500-in.  600- in. 

8s.  6d.  10s.  6d.  12s.  6d. 

1687  Verie's  or  Veroe's  Malt  Gauging  or  Ullaging  Rule,  Two 

Slide 9-inch,  8s.  6d. ;  12-inch,  10s. 

Ivory  Gauging  Rules  made  to  order. 

FIG.  1688. 


1688  Chrondrometer,  or  Corn  Balance,  for  ascertaining  the  differential  value  of 
Corn,  Barley,  Malt,  Seeds,  &c. ;  in  mahogany  box,  with  instructions  for 
use,  and  Table  of  average  weights  of  grain  and  seeds  (fig.  1234) : — 

ithofapint ;      ..        .        .        .220 

i        „  .     ' 2  12    6 



1689  Carpenters'  Rules,  Boxwood,  2-feet,  2-fold    .        .        .  £0    2    6     £0    3    6 

1690  Ditto        ditto      best  Boxwood,  2-feet,  4-fold  and  joint    0    4'    6        086 

1691  Pocket  Rules,  Boxwood,  1-foot  folding  .        .        .        .020        046 

1692  Ditto        ditto  Boxwood,  2-feet,  best,  full  divided          .    0  10    6        0  12    6 

1693  Pocket    Rules,   Ivory,  1-foot  folding,   German  silver 

mounts  .  ' 086        0126 

1694  Ditto        ditto        full  divided 0  16    0        150 

1695  Ditto        ditto        2-feet  folding,     ditto        ditto     16s.     150        1  10    0 

1696  Pocket  Rules,  Ivory,  four-fold,  full  divided,  in  case        .220        2  10     0 

1697  Ditto    ditto,    French  Metre,  divided  to   Decimetres, 

Centimetres,  and  Millimetres;  on  the  reverse  side 
the  English  yard — inches  and  l-8ths,  and  on  the  edge 
French  inches  and  lines,  4-fold,  best  Boxwood  .  .  0  16  0  110 

1698  Improved  Engineers'  Slide  Rule,  in  Boxwood,  for  cal- 

culating,  squaring,   &c.,    with  Routledge's  book  of 

instructions          .         .         .  .      10s.  6d.     0  12     6        110 

1699  Ditto        ditto,    in  Ivory 220        2100 

1700  Ivory   Pocket  Rule,  12-inch  four-fold,  with  English, 

French,  Spanish,  and  Rhineland  scales       .         .        .  0  12     6 

1701  Hull  Callipers,  for  Square  timber  measuring,      12-inch  1  10    0 

1702  Bow        ditto        Round  ditto  10-inch  0  18    6 

Larger  sizes  of  these  Callipers  at  about  Is.  6d.  to  2s. 
per  inch,  according  to  size. 

1703  Timber,  Plank  and  Cubing  Rules,  Measuring  Rods, 

and  Tapes  marked  with  inches  and  quarter  girt          .        various  prices. 

1704  Scribing  Iron .        .        .036       056 

1705  Rope  Gauge,  Boxwood  and  Brass 086 

1706  Ditto        ditto        German  Silver  and  Ivory          .  0  15    6 

1707  Rule  or  Gauge  for  Measuring  Horses,  to  close  up  in 

the  form  of  a  walking  stick         .....  110 

1708  Cattle  Gauge,  with  Tape  Measure,  giving  solid  contents  086 

1709  Radii  Curves  cut  to  order  in  Yulcanite,  Brass,  or  German  Silver,  any  radius 

up  to  100  feet. 
Templates  of  Rails  made  in  Metal  to  order. 


1710  Cavalry   Sketching  Board,  fitted  with  rollers  for  con- 

tinuous paper,  7  by  7|  inches    .    ^    .  170 

Larger  sizes  supplied  to  order. 

1712  Plane   Table,  simple  form,  as  used  by  the  School  of 

Military  Engineering 880 

1713  Plane  Table,   Mahogany,  with  Compass   and  Sighted 

Rule  and  Tripod  Stand 10  10  0 

1714  Ditto        ditto        Best  Mounted,  with  Telescope          .  24  10  0 

1715  Standard  10-foot  Rods,  Pine,  inlaid  with  Brass    .  2  17  0 

1716  Steel  Band  Chain,  in  Metal  Frame  mounting,  50  feet 

£1  14s.,  100  feet    ....  ...  2  10     0 

1717  Standard  Yard  of  German  Silver,  in  Pine  Case,  plainly 

divided 6  10    0 

1718  Ditto       ditto       German  Silver,  fully  divided  English 

and  Metric  Scales,  with  Thermometer,  in  Mahogany 

Box 12  12    0  to  25    0    0 


£    s.    d. 

1719  Stadiometer,  as  used  in  the  Army -  300 

1720  Spherometer,  to  measure  the  diameter  of  bullets,  &c., 

divided  into  O'OOl  of  an  inch  and  millimetres     .  5  10     0 

1721  Wire  Gauge   of  German  Silver,  for  measuring  the 

diameter  of  Wires  to  '001  of  an  inch  ....  1  15     0 

1722  Ditto        ditto        of  larger  size,  to  measure  to  -01  of  a 

millimetre  or  '001  of  an  inch 1  15     0 

1723  Patent  Wire  Gauge  (Milner's),  to  read  outside  and  inside 

to  '002  of  an  inch,  circular  form  ....  2  10    0 

1724  Ditto        ditto        flat  form 330 

1725  Off- set  Rod,  shod  with  Point,  10 -link      ....  040 

1726  Ditto        ditto        10-link  to  part  in  centre  with  Point 

and  Hook 096 

1727  Ditto        ditto        10  feet,  jointed,  to  part  in  centre, 

ends  plain  ferrules 0  11    0 

1728  Pickets  or  Ranging  Poles,  painted  three  colours,  with 

Iron  Strap  Shoes,  6  feet        .        .         .          per  dozen  1  15     0 

1729  Ditto        ditto        8  feet  ....         per  dozen  220 

1730  Ditto        ditto        10  feet 3  10    0 

1731  Flags,  White  and  Red,  fixed  to  Picket  Poles  or  loose, 

per  dozen  6s.,  9s.,  11s.  6d.  and 0  16    6 

1732  Sounding  Chain,  Stout  Iron,  welded  inch  links  with 

heavy  lead  (in  Stout  Case)  50  feet  £7  7s.,  100  feet      .  11    0    0 

1733  Sounding  Lines  for  Coast  Survey,  with  weight,  50  feet,  110 

1734  Ditto        ditto        100  feet 1  10    0 

1735  Negretti   and  Zambra's    Improved   Portable    Helio- 

graphs, for  Military  Signalling,  Surveying,  &c. 

3  inch,  per  pair     10  10     0          8  inch,  per  pair    17  17     0 
5    „          „  14  14    0          10    „        „  25    0    0 

1736  Lanterns  on  Stands  for.Night  Signalling,  with  key  and 

shutter each  550 

1737  Heliostat  Spencers,  local,  with  one  Mirror      ...  990 

1738  Torpedo  and  G-un  Directors  as  specially  constructed  by  Negretti  and  Zambra 

for  the  Admiralty  and  her  Majesty's  Navy.     Supplied  to  order. 


In  the  present  age,  when  so  many  calculations  are  required,  it  is  a  matter 
of  surprise  that  mechanical  aids  to  abridge  the  mental  labour  involved  are  not 
more  used.  The  efforts  made  by  inventors  and  manufacturers  to  perfect  machines, 
and  the  numbers  that  have  been  made,  proves  that  many  are  alive  to  the  facilities 
they  afford  ;  but  it  is  undeniable  that  calculating  machines,  and  foremost  among 
them  the  Arithmometer,  are  not  so  generally  employed  as  their  utility  warrants. 
When  it  is  considered  that  by  means  of  the  Arithmometer  long  operations  in  the 
fundamental  Rules  of  Arithmetic  can  be  performed  with  rapidity,  unfailing  accuracy, 
and  without  appreciable  mental  effort,  it  should  be  in  general  use  by  Accountants, 
Astronomers,  Bankers,  Electricians,  Engineers,  Surveyors,  Merchants  and  others. 
Members  of  the  Actuarial  profession  early  discovered  the  benefits  to  be  derived 
from  the  use  of  the  Arithmometer,  and  they  have  constructed  sets  of  Tables,  and 
made  other  calculations  on  it  for  some  years  past. 

As  an  instance  of  the  rapidity  with  which  results  may  be  obtained,  it  may  be 
mentioned  that,  with  the  improvements  lately  introduced,  eight  figures  can  be 
multiplied  by  eight  figures  in  about  fifteen  seconds,  and  larger  operations  in 

45,    CORNHILL,    E.G.,   AND    122,    REGENT    STREET,     W.,    LONDON. 








Giving  the  product  of  12  figures,  Complete  for  use  with  Quotient 



Ditto  ditto,  16  figures      24    0    0  Ditto  Ditto,  20  figures 

Instructions  for  use  sent  with  the  Instrument. 

£17  17 

38    0 






A  New  and  Revised  Edition,  Illustrated  with  Seventy-five  Wood  Engravings. 










Price  (Post  Free)  One  Shilling. 

A  detailed  description  of  Lanterns,  Slides,  and  Apparatus  with  practical 
instructions  for  their  use  will  be  found  in  the  above  Lantern  Manual,  on  the  pages 
indicated  at  the  top  of  each  section  of  the  List. 

Special  List  of  Negretti  &  Zambra's  Photographic  Views  for  the  Lantern 
supplied  upon  application. 


FIG.  1739.  FIG.  1740*. 



(Page  7.) 

1739  Magic  Lantern  and  one  dozen  Comic  Sliders,  in  a  box  with  about  fifty 

figures—  (fig.  1739) 

No.  1.  No.  2.  No.  3.  No.  4.  No.  5. 

7s.  6d.  10s.  6d.  23s.  30s.  42s. 

1740  Extra  Slides  for  above  :  4s.  6d.     5s.  6d.     12s.  6d.    16s.     21s. 

1740*  Magic  Lantern  No.  6,  in  a  box,  with  Solar  Argand  £    s.    d 

Lamp,  one  dozen  Comic  sliders  (fig.  1740°)        .  330 

1741  Astronomical  Slides  for  above  Lanterns  : — 

No.  1.  No.  2.  No.  3.  No.  4.  Nos/,5  &  6. 

11s.  13s.  30s.  40s.  50s. 

1742  Views  suited  to  Nos.  4,  5,  and  6      .        .        .       2s.  6d.    0    3    0        046 

1743  Comic  Slip  Slides  for  Nos.  4,  5,  and  6     ...  each    016        020 

1744  Estimate  A. — No.  6  Magic  Lantern,  with  a  selection  of 

Sliders  sufficient  for  an  entertainment,  including  a 
box  of  12  Humorous  slides,  about  50 figures  :  6  moving 
Comic  slides,  a  Fairy  tale  6  slides,  1  Chromatrope, 
and  one  of  Negretti  and  Zambra's  Photographic 
Statues 550 

1745  Estimate  B. — A  similar  set  to  the  above,  but  with 

6  additional  Coloured  Views,  1  Lever  Slide,  and  2 

Negretti  and  Zambra's  Photographic  Statues    .        .  6  16    0 

PHANTASMAGORIA  LANTERNS.— (pp.  12  to  22.) 


1746  Phantasmagoria  Lantern,  same  size  as  No.  6,  with  a 

Microscope  to  attach  to  front,  and  six  Microscopic 

Objects,  Water  Trough,  &c.,  in  case    ....  550 

1747  Superior  Phantasmagoria  Lantern,  with  two  Condensing 

Lenses  3-inch  diameter,  mounted  in  Brass  Cells,Sli ding 
tubes  for  adjusting  the  focus,  Fountain  Argand  Lamp 
and  Reflector,  &c.,  complete ;  will  give  a  disc  of 
8  feet  diameter 2  12  6 

1748  Ditto        ditto    with  Rackwork  Adjustment         .  300 



FIG.  1750. 

FIG.    1751 

1749  Very  Superior  large -sized  Phantasmagoria  Lantern, 

with  34-inch  condensing  lenses,  sliding  tube  for 
adjusting  the  focus,  improved  Fountain  Argand 
Lamp,  with  Reflector  complete,  of  the  very  best 
construction ;  to  show  a  3-inch  painting  on  a  disc  of 
10  feet  diameter  (fig.  1750) 

1750  Ditto        ditto  with  Rackwork  adjustment 

1751  Ditto        ditto,  4-inch,  with      ditto        ditto  (fig.  1751) 

Each.  Each. 

£    s.  d.       £    s.    d. 

3  12    6 


These  Lanterns  are  so  much  improved,  and  used  with  such  facility,  that  they  may  be  recommended 
with  the  greatest  confidence,  giving  a  perfectly  defined  figure,  with  a  well  illuminated  fiel  o  view,  from 
6  to  10  feet  in  diameter.  Combined  with  Negretti  and  Zamtora's  Coloured  Photographic 
Slides,  they  present  a  delightful  mode  of  instruction  with  amusement.  To  Schools,  Mechanics' 
Institutes,  &c.,  they  offer  peculiar  advantages,  and  are  extensively  used  by  the  conductors  of  these 
institutions  for  illustrating  almost  every  branch  of  scientific  information. 

1751*  Estimate   for   Sets   of  Lantern   Sliders. — a  box  of 

12  best  Comic  sliders,  12  movable  Comic  slip  slides, 

2  sets  of  Fairy  stories,  2  best  Chromatropes,  2  lever 

sliders,  6  Coloured  views,  and  3  Negretti  and  Zambra's 

Photographic  Statues. 

"With  Phantasmagoria  Lantern  as — 

No.  1749  ....... 

No.  1750  ditto        ditto 

No.  1751  ditto        ditto 

A  Microscope  adapted  to  the  above  Lanterns,  at  £2    2    0  additional,  will 

show  small  objects  brilliantly  enlarged  on  a  disc  4  feet  in  diameter. 
Balsam-Mounted  Microscopic  Objects,  suited  for  above,  2s.  to  2s.  6d.  each. 



11  11 

12  12 
14  14 

1754    An  Improved  form  of  Paramn  Lamp  can  be  supplied  with  the  Lanterns 
Nos.  1749  to  1751,  in  place  of  Oil  Lamps,  as  described  on  future  pages. 

45,    CORNHILL,    B.C.,    AND    122,    BEGENT    STREET,   W.,    LONDON. 


FlG.   1755 

1755  The  Bijou  Magic  Lantern  and  Slides.  Improved  Shape  Mineral  Oil  Lantern, 
fitted  with  Brass  Paraffin  Lamp,  with  Reflector  and  Lamp  Glass,  12  Slides 
comprising  4  Comic,  4  Nursery  Tales,  and  4  Mechanical  Slides,  in  all  36 
Subjects,  complete  in  Box, 

No.  1.  2.  3.  4.  5. 

12s.  6d.        18s.        26s.        32s.  6d.        37s.  6d. 

FIG.  1756. 

1756     Ditto        ditto        larger  sized  Lantern,  with  24  superior  Slides,  72  Subjects, 
complete  in  Box,(fig.  1756) 

No.  1. 







2  A 


45  r. 





No.  1.     Comprising  Improved  form  of  Lantern  to  burn  Paraffin  or  Mineral  Oil, 

3-inch  Condenser,  with  a  selection  of  24  Various  Slides,  consisting  of  a 

Fairy  Tale,  Moving  Comic  Slides  and  Yiews,  in  Box      .        .        .£440 
No.  2.    Ditto  ditto  ditto        with  3|-inch  Condenser  and  a  selection  of 

36  Slides,  and  1  Chromatrope  in  a  Box  ...  .        .    5  10    0 

No.  3.    A  Pair  of  Improved  Lanterns  as  above,  with  Paraffin  Lamps  and  a  selection 

of  Slides  as  No.  2,  and  4  Sets  of  Dioramic  Yiews,  in  a  Box  .        .  12  12    0 
This  Set  forms  a  very  Complete  Entertainment  for  Parlour  Use. 

FIG.  1758. 


The  enchanting  optical  effect  termed  Dissolving  Views  is  produced  by  means 
of  two  Phantasmagoria  Lanterns,  so  arranged  on  a  stand  that  the  centre  of  the  discs 
or  pictures  projected  by  each  are  coincident,  and  the  dissolving  or  blending  of  the 
pictures  is  effected  by  a  contrivance  in  front  of  the  two  Lanterns,  which  gradually 
shuts  off  the  image  thrown  from  one  Lantern,  whilst  the  other  becomse  gradually 
clearer,  until  a  perfect  picture  is  seen  on  the  disc ;  a  fresh  picture  being  put  into 
the  darkened  lantern,  the  action  is  reversed. 
1758  Dissolving  View  Apparatus,  adapted  for  parlour  use,  £  s.  a.  £  s.  <L 

consisting  of  two  of  Negretti  and  Zambra's  Superior 

Lanterns  of  Japanned  Metal  with  Rackwork  adjust- 
ment to  the  front  Lenses,  mounted,  with  Dissolving 

Apparatus.    Fig.  1758,  or  mounted  as  fig.  1765,  page 

358.     In  this  arrangement  the  views  are  exhibited 

with  clearness  and  brilliancy  on  the   screen,  from 

6-feet  to  10-feet  diameter,  by  improved  Fountain 

Argand  Oil  lamps  and  Reflectors.     It  is  simple  in 

use,  and  well  adapted  for  private  exhibition        .        .880      10  10    0 

Messrs.  Negretti  and  Zambra  can  confidently  recommend  the  Apparatus  at  £10  10s.  as  being  of  the  most 
improved  construction,  and  particularly  adapted  for  the  purpose  of  instruction  or  amusement,  where  the 
expense  or  trouble  of  the  Oxy-Calcium  or  Oxy-Hydrogen  Light  cannot  be  undertaken.  If  desired,  Paraffin 
lamps  can  be  supplied  to  these  Lanterns,  as  mentioned  on  the  previous  page,  in  place  of  Oil  Lamps. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  1759. 

1759  Improved  form  'of  Three-Wick  Russian  Iron  Paraffin  Lantern,  with  4-inch 
Condensers,  Achromatic  front  Lens,  with  Back  .vork  adjustment,  in  Box 
(fig.  1759) .  .  .  £4  10  £0 

FIG.  1760. 

1760    Ditto        ditto        fitted  with   Polished  Mahogany  Body,  4-inch 

•Condensers,  Achromatic  front  Lens,  &c.,  &c.,  (fig.  1769)      .        .    5  10    0 

2  A2 


FIG.  1761. 

1761  Dissolving  View  Apparatus,  consisting  of  two  Improved  Three  Wick  Paraffin 

Lanterns,  with  4-in.  Condensers,  A  chromatic  Front  Lenses,  with  Hackwork 
Adjustments,  and  Dissolver  in  box  .        .        .        .        .        .      £12  12    0 

1762  Ditto  Ditto,  best  Mounted  with  Mahogany  Bodies  to  Lanterns 

and  all  Brass  Fronts ,        .        .        .      £16  16    o 

These  Improved  Lanterns  No.  1761  can  be  supplied  with  either  Oxy-Calcium 
or  Oxy-Hydrogen  Burners.  Prices  given  upon  application. 

(Page  61.) 

1763  An  Extensive  [Stock  of  Hand  Painted  .Views  of  all 
parts  of  the  World,  3^-inch  Circles,  adapted  for 
either  the  Single  Lantern,  or  Dissolving  View 
Apparatus 8s.  0  10  6  150 

These  paintings  differ  materially  from  the  common  lantern  slides,  requiring  first-rate  artistic  talent 
to  make  them  effective,  as,  owing  to  the  intensity  of  the  light,  the  slightest  defect  is  developed.  They 
therefore  require  the  most  scrupulous  care  with  regard  to  the  minutest  details.  Subjects  may  be 
painted  to  suit  the  taste  or  view  of  the  purchaser,  varying  in  price  according  to  the  subject  and  size  of 
the  painting. 

Slides  carefully  painted  from  Drawings  or  Photographs  to  order. 
Engravings,  Drawings,  Maps,  &c.,  copied  by  Photography  for  the  Magic  Lantern,  &c. 


Seepages  365  to  368. 

45,    CORNHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG.  1764. 


1764  The  great  advantage  of  this  Lantern  is,  that  by  means  of  its  double  changing 
holder,  working  vertically,  any  framed  slides  (such  as  Rack  work,  Lever  Action, 
Changing  Comic,  &c,)  can  be  shown  one  after  another  without  any  interval,  thus 
doing  away  with  the  unsightly  white  disc  of  light  seen  on  the  screen  while 
changing  the  slides  in  the  ordinary  single  Lantern. 

With  the  Patent  Lantern  any  Mechanical  Slide  can  be  introduced  into  a  Lecture 
set  of  Photographic  Slides  used  with  a  carrier  frame,  without  taking  out  the  carrier, 
by  simply  placing  the  Mechanical  Slide  in  the  bottom  stage  and  raising  it  when 
required  into  position,  and  then  lowering  the  stages  again  to  their  former  position  ; 
without  having,  during  the  change,  shown  any  white  light  on  the  Screen,  which 
is  impossible  to  do  with  an  ordinary  single  Lantern. 

The  Changing  Holder  is  raised  and  lowered  by  a  Lever  which  enables  the 
operator  to  either  raise  it  slowly,  so  as  to  make  the  Slides  exhibited  appear  like 
a  Panorama,  or  to  raise  it  so  quickly  that  the  change  from  one  slide  to  another  is 
almost  imperceptible. 

The  Patent  Lantern  is  fitted  with  a  4-inch  Condenser  and  Achromatic  Com- 
bination Front  Lens,  with  large  size  lenses  to  the  back  combination  (thus  giving 
greater  light)  and  double  pinions  to  the  rack  adjustment.  It  has  a4-wick  Paraffin 
lamp,  with  wicks  2  inches  wide  (arranged  to  form  2  wedges,  thus  W,  this  preventing 
the  flicker  of  the  wicks,  seen  on  the  Screen,  when  they  are  placed  parallel  to  one 
another),  and  a  tall  jointed  Chimney,  complete  in  Box.  (fig.  1764)  Price  £880 

Prize  Medal,  1851.     Honourable  Mention,  Paris,  1855. 



FIG.  1768. 


$.  Negretti  and  Zambra  would  call  especial  attention  to  the  Oxy-Calcium 
Light,  which,  at  a  trifling  advance  on  the  expense  of  the  best  Argand  Oil  lamps, 
gives  a  light  very  nearly  equal  to  the  Oxy-hydrogen  Light.  It  is  perfectly  safe, 
easily  managed,  and  occupies  small  space;  very  cleanly  in  use,  all  grease  and  smoke 
being  avoided.  With  the  Oxy-Calcium  Light  a  brilliantly  illuminated  disc  may  be 
obtained  14  to  16  feet  diameter. 

1765    A  best  Phantasmagoria  Lantern,  with  3|-in.  Condensing  Lenses, 
with  Hackwork  Adjustment  to  front  Lenses,   fitted  with  the 
Oxy  -  Calcium   Light.       Apparatus  for  making  the   Oxygen   gas, 
Gas  Bag,  and  Pressure  Board,  Conducting  tube,  &c.,  complete; 

in  box 

A  ditto     ditto     with  four  4-inch  Condensing  Lenses,  &c.,  com- 
plete ;  in  box 


£    a.    d. 


11  11    0 


FIG.  1770. 

1767  Oxy-Calcium  Light  Dissolving  View  Apparatus,  fitted   with    condensing 

lenses,  3^-inch  diameter,  complete  with  apparatus     .         .         .       £14  14s. 

1768  Ditto        ditto        with  Rackw.ork  Adjustments  (fig.  1768)    .         .       £15  15s. 

1769  Dissolving  View  Apparatus,  fitted  with    Oxy-Calcium  Light,   condensing 

lenses,  4-inch  diameter,  Hackwork  Adjustments,  complete  with  apparatus, 

£17  17s. 

Argand  Oil  Lamps  are  supplied  with  the  above  marked  thus  *  for  use  when  the  Oxy-Calcium  Light  is 

not  convenient. 


The  Lanterns  ISTos.  1765  and  1767,  and  Dissolving  Yiew  sets  1758  to  1761,  can 
be  fitted  with  the  Oxy-Calcium  Gas  jets  (as  shown  fig.  1776),  in  place  of  the  Spirit 
Burners  at  the  same  cost. 

The  light  obtained  by  this  arrangement  is  almost  equal  to  the  Oxy- Hydrogen, 
and  is  Quite  Safe.  Wherever  Coal  Gas  is  laid  on  to  the  house  or  building  we 
should  advise  the  use  of  this  jet,  being  far  superior  to  the  Oxy-Calcium ;  but  where 
pictures  of  more  than  20  feet  diameter  are  desired,  the  Oxy-Hydrogen  Light 
must  be  used. 


1770  Dissolving  View  Apparatus,  illuminated  by  the  Oxy-Hydrogen  Lime  Light, 

giving  a  brilliant  and  distinct  picture  on  the  disc  30  feet  diameter. 
Consists  of  two  Mahogany  Lanterns  with  best  condensing  lenses,  4^-inch 
diameter,  Brass  fronts  and  slide  holders,  mounted  on  a  stand ;  dissolving 
apparatus^  improved  Oxy-Hydrogen  Jets  and  Limeholders ;  flexible  con- 
necting Tubes,  with  stopcocks;  gas-bags  with  Pressure  Boards;  Hydrogen 
Generator  and  Purifier;  Oxygen  E/etort  and  Conducting  Tubes,  &c} 
complete  with  Clock  Work  Motions  (best  manufacture),  adapted  to  the 
limeholders,  for  keeping  the  lime  cylinders  slowly  revolving  and  exposing 
a  fresh  surface  to  the  action  of  the  gases.  The  best  form  of  Apparatus 
for  Exhibiting  the  Photographic  Views  (fig.  1770)  .  .  .  £47  0  0 

This  Apparatus  is  supplied  either  as  shown  in  fig.  1770  or  fig.  1765  as  may  be 

Dissolving  View  Apparatus,  fig.  1768,  if  mounted  with  Mahogany  Lanterns, 
as  fig.  1770,  will  be  42s.  the  pair  extra. 



FIG.  1771. 


1771  Mahogany  Lantern  Lined  with  Tin  (as  fig.  1771),  having  3|  inch  Condensing 

Lenses,  Brass  Mounts  to  Front  Lenses  with  Rackwork  Adjustments, 
Japanned  Tin  Sliding  Front  to  vary  distance  between  Lantern  and  Screen. 
Complete  with  Apparatus  for  making  and  purifying  the  Gas.  Full  size 
Gas  Bags  and  Pressure  Boards.  Flexible  conducting  Tubes  and  Con- 
nectors, &c.,  &c.  To  give  a  brilliant  Disc  of  12  to  16  feet  in  diameter 
from  Paintings  3i  inch  diameter  .  .  .  .  .  .  £27  0  0 

1772  Ditto  ditto  as  above,  but  with  4-inch  Condensing  Lenses  for  producing  a 

Disc  of  16  to  20  feet  diameter £31  10    0 

Handsome  Brass  Fronts  to  either  of  the  above  Sets  with  Extra  Lenses  and 
mountings  for  projecting  a  smaller  picture  at  great  distance. 

each  extra    £300 

The  arrangement  of  Lanterns  (as  fig.  1771)  can  only  be  effectively  used  with 
the.Oxy-Hydrogen  Lime  Light,  the  vapour  or  smoke  given  off  in  the  lower  Lantern 
injuriously  affecting  the  Light  in  the  upper  one. 


1772  Negretti  and  Zambia's  Improved 
Tri-Unial  Lantern  (fig  1772)  for  ex- 
hibiting Dissolving  Yiews  and  Effects 
by  the  Oxy- Hydrogen  Lime -Light. 
Best  4-inch  Condensers.  Polished 
Mahogany  Lanterns,  with  Brass  Fronts, 
Hackwork  and  Sliding  Tubes  for  adjust- 
ing the  Front  Lenses  for  varying 
distances^from  the  screen.  A  set  of  3 
Achromatic  Lenses  being  supplied 
giving  pictures  at  a  range  of  from  20 
to  120  feet. 

Price    for    the     set    in    its     most 


complete  form,  including  Gas  generat- 
ing and  Purifying  Apparatus,  2  stout 

y  Gas_Bags,[&c.,  &c.  (fig.  1772) 

Price  £46  10    0 

FIG.  1771 
FIG.  1773. 

1773  Improved  Apparatus  for  exhibiting  OPAQUE    OBJECTS,   magnified  by 

the    Oxy-Hydrogen   Light,    upon    a    Screen    in    their    natural    colours 
(fig.  1773),  Complete  £26     5    0 

1774  The  Aphengescope,  a  small  modified  arrangement  of  the  above  Apparatus, 

adapted  for  use  with  a  pair  of  Dissolving  Yiew  Lanterns        .£220 
Ditto        ditto        for  a  Single  Lantern  (fig.  1774)        .        .         .         0  18     6 

These  effects  can  only  be  well  exhibited  by  the  Oxy-Hydogen  or  Oxy-Calcium  Lights. 


No.  1775. 

No.  1776. 


No.    1779. 

No.  1784. 


45,    COENHILL,    E.G.,   AND    122,    EEGENT    STREET 

W.,    LONDON.  363 

(Pages  of  Lantern  Manual,  19  to  93.) 

£    s.    d. 

1775  Oxy-Calcium  Spirit  Lamp'       .       .       .         (page  24) 

1776  Oxy-Calcium  safety  Gas  or  Blow-through  Jet  (  „    31) 

1777  Oxy-Hydrogen  Burner  with  Platinum  Jets     .  (   „    32) 

1778  Oxygen  Retort ,       .  (    „    24) 

1779  Ditto        ditto       Stout  Copper,  with  Cap  and  Flexible 


1780  Hydrogen  Generator,  Stout  Lead  (page  of  Book  34) 

1781  Zinc  Purifier     ....       Do.        do.        .. 

1782  Copper  ditto,  Stout 

1783  *Gas  Bags  for  Oxy-Calcium  Light          .        .  (page  42) 

1784  *Ditto       ditto       Large  and  Stout,  for  Oxy-Hydrogen 

Light  (fig.  1784) (page  42) 

1785  Pressure  Board  (fig.  1785)        ....  (page  29) 

1786  Flexible  Tube  i-in.  inside  (page  38)        .        .    per  foot 

1787  Barker's  Safety  Valves  for  Oxy-Hydrogen  Light,  each 

1788  Cog  Wheel  Lime  Adjuster  (registered)  to  Nos. 

1789  Mahogany  Slide  Holders  for  Photographic  Lantern 

Yiews perdoz.  0 

1790  Improved  Oxydating  Lamp  Glasses       .       .    per  doz.  0 

1791  Opaque  Screens  of  Oil  Cloth,  from  3  to  9  yards  square,  made  to  order. 

1792  Transparent  Screens  of  all  sizes,  (page  63). 

8-ft.  square,  21s  ,  10-ft.  square,  25s.,  12-ft.  square, 
35s.,  20-ft.  feet  square,  105s. 

£    s. 

0  15 

1  5 

2  0 
0  15 

1  1 
0  13 

0    7 
0  12 

2  15 


4s.  each  extra. 

FIG.  1793. 

FIG.  1793.* 

Portable  Frames  for  Screens,  in  Box  (figs.  1793  and 

1793*) 42s.    2  10    0 

Oxygen  Gas  Mixture,  variable         .        .        .       per  Ib. 

Best  Lime  Cylinders  for  Oxy-Calcium  Light     per  bot.    036 

Ditto        ditto        for  Oxy-Hydrogen  Light  .         .        .050 

Magnesium  Wire per  foot 



1798^  Glass  Water  Trough 

All  the  Accessories  and  Scientific  Apyarati 
figured  in  the  Lantern  Manual,  supplied  to  order. 

'  for  use  nith  the  Lantern  as  described  and 

(See  No.  1095,  page  282.) 


SLIDES  FOR  MAGIC  LANTERNS.— Cpp.  48  to  62,) 







FIG.  17  yy. 

Large  size  Best  Comic  Slides,  One  Dozen  in  box,  about    £ 
fifty  figures  (fig.  1799) 2 

Fourteen-inch    ditto 1 

Twelve-inch        ditto        ....... 

Fairy  and  Nursery  Tales,  painted  on  three-inch  circles  :— 
Cinderella,    Robinson    Crusoe,     Blue     Beard,    John 
Gilpin,  Robin  Hood,  Jack  the  Giant  Killer,  Jack  and 
the  Beanstalk,  Tale  of  a  Tub,  Whittington  and  his 
Cat,  St.  George  and  the  Dragon,  &c.,  &c. 

Per  set  of  eierht.  ten.  or  twelve  slides    £1  Is.     1 





FIG.  1805. 

Astronomical     Sliders,    for    illustrating    the    various 

Phenomena  of  the  Heavens,  with  Descriptive  Book, 

for  the  Phantasmagoria  Lantern  ....  220 

Ditto  ditto  for  the  Second  Size  ,  330 

Ditto  ditto  for  the  Large  Size  (fig.  1805)  .  440 

A  Series  of  Ten  Finely-painted  Astronomical 

Diagrams,    with    Rack    and    Pinion    Movements, 

by  which  the  images  produced  are  made  to  revolve ; 

In  Box— for  Phantasmagoria  Lanterns  .  660880  10100 
Sets  of  Natural  History  Slides,  consisting  of  correct 

drawings  of  Mammalia,  Birds,  Fishes  and  Reptiles  42s.  330  440 
Geological  Slides,  showing  the  Earth's  Strata,  with 

figures  of  Fossil  Animals  and  Plants  ....  440 

Photographic  Portraits  of  Celebrated  Individuals,  in  Frames  036 

FIG.  1810  FIG.  1810*. 

1810  Comic  Movable  and  Shifting  Glass  Slides,  (or  Slip  Slides)— a 
diversity  of  Subjects,  by  which  the  magnified  images  appear  to 
have  life  and  motion  (figs.  1810,  1810*)  .  Is.  6d.  2s.  2s.  6d.  0 

3    6 

45,    CORNHILL,    E.G.,   AND   122,   REGENT    STREET,   W.,   LONDON.  365 

FIG.  1811. 

£     s.     d  £     s     d 

1811    Panoramic .  Landscapes,  Marine  Views  and  Railways,  with  Moving  Figures, 
Shipping,  Railway  Trains,  &c.  (fig.  1811)  .        7s.  6d.      0  10    6        0  16    0 

FIG.  1812. 

FIG.  1815*. 









Lever  Slide,  representing  the  movements  of  Animals, 

Birds,  &c.,  such  as  a  Stag  or  Swan  drinking  5s.  6d.  0  6  6  0  10  6 
Mechanical  Slide  representing  a  Dog  Begging,  with 

a  pipe  taken  from  the  mouth   of   his   master  and 

placed  in  the  dog's  mouth    ......  0  12     6 

Ditto  ditto,  with  moving  Smoke  effect — two  slides  150 

Mechanical  Slide,  representing  the  Bat  Eater  .  0  12  6 

Chromatropes,  (best  painting)  a  variety  of  Beautiful 

and  Brilliant  Designs  (fig.  1815*)  .  .  .  .  0  11  6  0  12  6 

Ditto,  Small 086 

Ditto,  with  Motto  or  Design  in  the  centre  .  .  .  0  14  0  0  16  0 
Rackwork  Slides,  to  represent  Wind  and  Water  mills 

in  motion  on  the  screen — best  paintings  .  .  .  0  12  6  0  14  0 
A  Rackwork  Slide,  to  show  the  Aurora  Borealis,  with 

a  Yiew  in  the  Polar  Regions 140 

A  Rackwork  Slide,  with  Yiew  and  Rainbow  Effect  .  110 

FIG.  1821. 

Rackwork  Fountain  Effect      .       .       .       .(fig.  1821) 
Kaleidoscope   for  the  Lantern,   for    Oxy-Hydrogen 

0  12    6        0  14    0 

2  10    0 


1823  Mechanical  Slide,  to  represent  the  Effects  of  a  Snow  £  s.   a.        £    s.  d. 

Storm 0  12  6 

1824  Ditto            ditto        Moving  Water,  simple  effect          .  0  10  6 

1825  Ditto  ditto        Shipping  with  Moving  Waves,  and 

Birds,  best  painting .  1  10  0 

1826  Ditto            ditto        for  Curtain  Effect          ...  0  lo  0 

1827  Ditto            ditto        an  Aquarium  with  moving  Fish    .  0  12     6         0  14  0 

1828  Ditto  ditto        a  Scene  at  a'  Fair,  with  moving 

Swing  (lever  motion) 0  10  6 

1829  Ditto  ditto        Destruction     of     Pompeii,     with 

Hackwork  Effect  .  0  12    6        0  14  0 


FIG.  A.  FIG.  B.  FIG.   c. 

They  are  arranged  in  sets  of  two,  four,  six,  and  sometimes  ten.  We  give  a  list 
of  a  few  of  the  most  striking.  Two  prices  are  quoted,  regulated  by  the  quality  of 
the  paintings  and  the  amount  of  fine  detail. 

The  following  prices  are  for  3i-inch  circular  paintings,  suited  for  the  3^  or 
4- inch  lanterns.  Larger  sizes  are  painted  to  order  at  proportionate  price. 

1830  Mount  Vesuvius. — Three  slides,  Day  and  Night,  and 

an  Eruption .140        1160 

1831  Ditto     ditto. — Three  slides,  with  Hackwork  to  exhibit 

the  Smoke  and  Lava  in  Motion  .  2  16    0 

1832  Rustic  Scene.— Three  slides,  Watermill,  Summer,  ditto 

Winter,  and  Moonlight        . 140        1  16    0 

1833  Rustic  Scene. — Three  slides,  Watermill  in  motion,  a 

Swan  moving  along  the  Water,  Summer  changing  to 
Winter  by  Moonlight ;  the  clouds  move,  lights  appear 
in  the  windows  of  the  mill,  with  ripples  on  the  water  330 

1834  Landscape. — Three  slides,  with  Rain  Storm,  Lightning, 

and  Rainbow  Effects     . 110        1  10    0 

1835  Castle  of  Chillon  by  Day  and  Night,  two  slides      .        .    0  16    0        150 

1836  The  Emigrant  Ship.— Six  slides.    The  Ship    leaving 

Port ;  at  Sea ;  Full  Sail  by  Moonlight ;  the  Storm ; 
Ship  struck  by  Lightning ;  Ship  on  Fire ;  the  Raft 
with  Survivors  ........  220 

1837  Ditto        ditto        with  Moving  Effects          .        .        .330        550 

1838  Mount  Ararat,  with  Rainbow  effect        ....  0  16    0 

1839  The  Soldier's  Dream.— Two  slides 0  16    0       150 

1840  Arctic  Regions. — Three  slides,  Mock  Sun  and  Aurora 

Borealis  effects 140        1160 

1841  Farm   House. — Three    slides,    Summer,    Winter    and 

Moonlight 140        1160 

45,   CORNHILL,    B.C.,   AND    122,    REGENT    STEEET,   W.,    LONDON.  367 

1842  Niagara  Falls.— Two  slides  with  Rainbow      .        .        .  £0  12    6      £0  15    6 

1843  St.  Peter's,  Rome.— Three  slides,  Day  and  Night,  with 

Fireworks  from  the  Tower  of  St.  Angelo    .        .        .140        220 

1844  Interior  of  ditto. — Two  slides  ditto  ditto,  with  effects   .  180 

1845  Milan  Cathedral  by  Day  and  Night,  two  slides     .        .  0  12    6 

1846  The  Rialto,  Venice  ditto  ditto  .  0  12    6 

1847  Holyrood  Palace  ditto          ditto  .  0  12    6 

1848  St.  Paul's  Cathedral          ditto  ditto  and  Interior  150 

1849  The  Old  Royal  Exchange,  London,  by  Day,  by  Night, 

on  Fire,  and  the  present  Royal  Exchange;  three 

slides ,        .        .        .        .1160        220 

1850  A  Storm  at  Sea  and  the  Life  Boat         .        .        .        .    0  16    0        150 

1851  Mount  Hecla,  with  Lava  and  Smoke  in  Motion,  two 

slides 1  12    0 

1852  The  Magician's  Cave  and  effect 1  10    0 

1853  The  Magic  Mirror.— Two  slides,  and  effect    ...  1100 

1854  Faust  and   Mephistophiles,   with   effect,   Vision   of 

Marguerite,  two  slides  ......  1  10    0 

1855  Mosque  of  Omar. — Two  slides,  Day  and  Night  effect    .  0  16    0 

1856  The  Four   Seasons,   Spring,  Summer,  Autumn,  and 

Winter . 1  12    0 

1857  The  Serenade.— Moonlight  Scene  with  Gondola    .        .  0  14    0        150 

1858  The  Angel's  Whisper.— Two  slides         ....  150 

1859  London.— St.  Paul's  and  the  Thames,  Day  and  Night  .  150 

1860  Virginia  Water,  Moving  Swan  and  Night  effect,  three 

slides    . 1  10    0 

1861  OsbornelHouse,  by'.Day  and  Night  and  effects,  Windows 

lit  up     .        .     '  .        . 0  18    6 

1862  Old  London  in  1666,  Day  View  and  the  great  Fire, 

with  Rackwork  effect,  Smoke  and  flames,  three  slides  220 

1863  The  Port  of  Alexandria,  with  Shipping  in   motion, 

Smoke,  Moonlight,  and  ripple  on  the  Water       .         .  1  10    0 

1864  Esquimaux   Village. — Snow  Huts,  with  Aurora,  &c., 

three  slides 110 

1865  The  Overland  Route. — A  series  of  twelve  views,  each 

view .080        0  12    0 

1866  Mount  Blanc. — A  series  of  eighteen  views.    The  Ascent 

from  Geneva  to  the  summit,  and  the   Descent    to 

Chamouni,  each  view 080        0120 

1867  The  Arctic  Regions. — A  series  of  twelve  views,  each 

view 0    8  "O        0  12    0 

1868  Natural  Phenomena.— A  series  of  eighteen  slides,  each 

view .080        0120 

1869  The  Bottle.— Eight  slides,  each  Painting       .        .        .    0  10    6        0  12    0 

1870  The  Drunkard's  Children. — A  series  of  views,  each 

painting 0  10    6        0  12    0 

1871  The  Pilgrim's  Progress.— A    series   of   twelve,    each 

painting 0  10     6 

1872  A  Journey  Round  the  World. — All  the  most  remarkable 

and  interesting   views  in  the  four   quarters  of  the 

Globe,  each  slide 080        0126 

Nos.  1865  to  1868.    These  series  can  be  extended  to  thirty-one  views  each,  and  with  No.  1872  will  be 

painted  to  order. 







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size  of  the  Slide. 


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45,    CORtfHILL,   E.G.,   AND    122,    REGENT   STREET,   W.,   LONDON.  3G9 




The  award  of  the  only  PRIZE  MEDAL  by  the  Jury  of  the  International 
Exhibition  of  1862  to  NEGRETTI  &  ZAMBRA'S  Photographic  Transparencies 
sufficiently  stamps  their  value  as  aids  in  the  advancement  of  Science  and  Education 
without  further  comment. 

The    following    extract    from    CHAMBERS'    JOURNAL    will    describe    these 
Photographs  exhibited  by  the  Lantern : — 

"Unquestionably,  however,  the  most  important  use  which  has  yet  been  made  of  this  new  process 
(illuminated  dissolving  Photographs)  was  the  exhibition  through  the  whole  of  the  winter,  at  the  Man- 
chester Mechanics'  Institution,  of  a  series  of  Egyptian  Photographs.  The  most  remarkable  feature  of 
these  series  of  pictures  was  the  solidity  and  reality  with  which  they  were  invested,  which  were  almost 
sufficient  to  cheat  the  beholder  into  the  belief  that,  by  some  optical  glamour,  he  was  transported  bodily 
to  the  mystical  banks  of  the  Nile.  Most  of  us  are  familiar  with  these  scenes  through  the  medium  of 
David  Roberts'  paintings,  but  whilst  we  willingly  pay  them  the  tribute  of  our  admiration,  gratefully 
remembering  the  pleasant  hoars  we  have  spent  in  studying  them,  we  must  admit  that  they  fall  short 
of  producing  the  interest  and  effect  which  result  from  Photographs  of  the  same  scenes  shown  in  this 

(See  also  Page  56  of  1ST.  &  Z.'s  Manual.) 

Negretti  and  Zambra's  Photographic  Lantern  Slides  include   Yiews  of  the 
most  remarkable  places  in  the  Globe,  Photographic  Statues,  &c.,  &c. 


Price  of  Photographic  Views,  printed  with  Albumen,  £    s.    d. 

Uncoloured,  mounted  in  Frame  each  026 

Ditto                              ditto        Coloured,                ditto        ditto  056 

Photographic  Statues   .       .       .       .               .    ditto       ditto  026 

Mahogany  Frames  or  Holders  for  above     .       .    ditto       ditto  006 



3    A  Nymph  preparing  for 
the  bath 
3c  Apollo    discharging     his 
4     The  Tired  Hunter 
4c  Eve  Listening 
5     Una  and  the  Lion 
5A  Dorothea 
6A  Jane  Shore 

GB  Maid  of  Saragossa 
7    Andromeda 
7*  A  Naiad 
9     Mercury 
10    Flora 
11     Boy  with  Tambourine 
12*  Venus 
13    Venus  Vincitrice 
14     Flora 




The  Laocoon 
Minerva  of  Farnese 

t  Messrs.  Negretti  and  Zambra  beg  to  caution  purchasers  of  Photographic  Slides  against  pictures 
printed  with  Collodion,  as  definition  and  clearness,  fit  for  exhibition,  are  only  to  be  obtained  from 
Albumen  prints. 

2  B 



33*  Children  and  Pony 
34    The  Emigrant 

37  Samson 
37*  Minerva 

38  Musidora 

39  The   Massacre  of   the 


40  Milo 
40*  Minerva 

41  Satan 

42  Ariel 
44*   David 

46  The  Mourners 

47  Andromeda 

47*  The  Borchesse  Flora  x 

48  Ulysses 

49  The  First  Whisper  of 


51  Sabrina 

52  Zephvr  and  Aurora 

53  Geoffrey  Chaucer 

54  A  Nymph  of  Diana 

55  Mercury 

56  Shakspeare 

57  Lavinia 

58  Highland  Mary 
62A  Diana 

62C  Night 
62o  Morning 

63  JEsculapius 

64  Psyche 
64*  Pomona 

66  A  Fawn  with  Cymbals 

67  Angel  watching 
67*  David 

63    Venus  and  Cupid 
75     Diana 

78     Cupid  and  Psyche 
'79     Thalia 

80  Zephyr  wooing  Flora 
80*  Augustus 

80A  A  Roman 

81  Apollo 
81*  A  Victory 

82  Penelope 

83  Venus  at  the  Bath 
83*  A  Bacchante 

84  A  Victory 

85  Penelope  and  Telema- 


89  Bacchus 

90  .ZEsculapius 
91*  A  Hunter 

92  Julian  the  Apostate 

93  The  Three  Fates 

94  The  Chase 

96    The  First  Cradle 

98  A  Neapolitan  Dancer 

99  A  Neapolitan  Improvi- 

100  Cain 



A  Day  Dream 

The  Dying  Gladiator 

Eve  at  the  Fountain 

101  A  Bather 

102  Milo  of  Crotona 

115  Eurydice 
115*  Charity 

116  Venus          disarming 


121     Charity 
120-29*  Pudicita 

130  Ceres 

131  Venus     leaving    the 

135     Mars  and  Venus 

155  Hope 
138    Magdalen 

152     The  Murder    of    the 

142*  A  Vestal  Virgin 

146  David 

147  A  Girl  Knitting 

148  First  Steps 

149  Italy 

150  Veritas 
150*  Eve 

152     Melancholy 

156  Esmeralda 
160     Ishmael 

162  Minerva  protecting  a 


163  A  Child  Christ 
155-65*    Juno 

167  A  Nymph 

168  A  Girl  bearing  Fruit 

169  A  Vase 

170  Pomona 

171  Medicine 

171A  Maria  F.  Malibran 

176  Homer 

177  Thucydides 

178  Guardian  Angel 
185-7-8     A  Victory 
191     An  Eagle 

195  Priest  of  Bacchus 

196  A  Pieta 
196*  Melpomene 

201     Madonna  of  Munich 
201*  A  Violin  Player 

201  Iris      Hecate     of 


202  A  Nymph 

204    Ceres  and  Proserpine 
308     Angel 
21 2     A  Knight 

223  Love 

224  Venus 

229  Julia 

230  Musician 
•  231     Victory 

232  A  Youth 
233B  Voltaire 
234  Camillus 

Love  Triumphant 


Toilet  of  Atalanta 


The  Greek  Slave 

239     Urania 

250  Psyche 

251  Belvidere  Apollo 
253     Eros 

255    Ariadne 
259     Iphigenia 
261-270     Diana 

262  Hagar 

263  A  Hunter 

2t)4     Hunter    defending  his 


265    Abraham  Duquesne 
267     A  Nereid 
269     Winter 
271     A  Flower  Girl 
279A  Chateaubriand 
286     Trajan 
295     A  Fawn 
308A  Louis.  XIV. 

313  Peter  Paul  Rubens 

314  Antinous 
321     Demosthenes 
327     Zeno 

385  GotholdEphraimLessing 

251     Pallas 

358     Cupid  encircled  by    a 

362    Venus  di  Medici 

3  7    A  Fawn 

374     Urania 

407     Shakspeare 

412*  William  Wordsworth 

431     Humphrey  Chetham 

449     Earl  of  Chatham 

0-1     Massacre     of     the 

0-2     Mattabuz  and  Camilla 

0-3    Aurora 

0-4     Sleeping  Children 

0-5     Godiva 

0-6    Ajax  praying  for  Light 

0-7    A  Girl  witi  Triangle 

0-8     Music's  Martyr 

0-9     The  Pieta  ;    by  Bermine 

0-10  The  Minstrel 

0-11  Michael  Angelo 

0-12  Jonah 

0-13,0-14,0-15    Virgin  and 

0-16  Marriage  of  Virgin 

0-17  Girl  with  Pet  Bird 

0-19  Bas    Relief— The    Last 

0-20  Bas  Relief — The  Adora- 
tion of  the  Magi 

0-21  Bas  Relief— Virgin  and 

'  0-24  John  Bunyan 

0-23  St.  George 

0-25  St.  Andrew 

0-26  St.  John 

Ancient  Briton 
A  Warrior 
The  Son  of  Niobe 

45,    COBTTHILL,    E.G.,    AtfD    122,    REGENT    STREET,    W.,    LONDON. 


Photographically  Printed  on  Albumen. 

309-2-28     Views  of  the  Temple  of  Dendera 

301     The  Granite  Quarries  of  Syene 

300-4    The  Rock  Temple  of  Derr,  the  chief 

town  in  Nubia 
305     The  Kock  of  Abouseer  and  the  second 


300     Kalet  Adde,  a  ruined  Saracenic  town 
307-9     The     Fagade    of    the    Great    Rock 

Temple  at  Aboo-Simbel  in  Nubia 

310  The   smaller  Rock    Temple  of    Aboo- 

Simbel,  time  of  Rameses  the  Great, 
B.C.  1400 

311  Girgeh,  Upper  Egypt 

312  The  Temple  of  Amada  near  Derr 
313,  314     The  Temple  of  Wady  Saboda 
315-317     The  temple  of  Dacke,  founded  by 

Ergamun,  about  2000  years  ago 
316    Temples  at  Makarraka  in  Nubia 
318-19     The  Portico  of  the  Rock  Temple  of 

Gerf  Hossayn  or  Gyrche 
320    The  Temple  of  Dendoor,  built  in  the 

reign  of  Augustus  Cgesar 
321-2-3-4     The  Temple  of  Kalabshee,  Nubia 
325    Traveller's  Nile  boat  or  "  Dahabeah  " 
326-7     Wady  Kardassy  in  Nubia 
229-30-31     Views  in  the  Island  of  Philse 
333-4     The   Principal   Court    of  the  Large 

Temple  at  Philas 

335  Crocodile  on  a  sand  bank  in  the  Nile 

336  Principal    Corridor  of  •  the   Island   of 

337-8    Views  from  the  Island  of  Philse 
339-41-42     Hypsethral    Temple    at     Philse. 

usually  called  "  Pharaoh's  Bed  " 
340    View  between  the  upper  portions  of  the 

Two  Principal  Pylons  at  Phil  SB 

343  View  of   an  Arab   Village   and  ruins, 

Island  of  Biggeh,  opposite  Philae 

344  Ruined     Mosque     of     Mishdd,     with 

distant  view  of  Philse 

345  Remarkable     Granite    Formation    be- 

tween the  first  Cataract  and  Philaa 

346  The  River  Wall  and  South  End  of  Philae 

347  North  Approach  to  Philas 

348  Assouan,  Upper  Egypt 

349-88     The  Sphinx  and  Great  Pyramid  at 


550-51     The  Temple  of  Kom-Ombo 
352-3-4     Grottoes  and  Rock  Cuttings  in  the 

Sandstone  Quarries  at  Hagar  Silisili 
355-56     Temple  of  Edfou,  Greek  Period 
357-8     The  Temple  of  Erment,  near  Thebes 
359-60-61     Views  of  Luxor 
362-3     The  Approach  to  Karnac,  the  Avenue 

of    Sphinxes,    and    the    Ptolemaic 


364-6-7     The  principal  Ruins  of  Karnak 
365     General  View  of  Karnak 
368-9     The  Two  Obelisks,  and  part  of  the 

Hall  of  Columns  at  Karnak 
370    Remains  of  the  Granite  Pylon  and  two 

Colossi  at  Karnak 
371-95-6-7-8-9       Six   views   of     the   tombs 

of  the  Memlook  Kings  at  Cairo 
372-3-4-93-4     Views    of     Portions    of    the 

Great  Hall  of  Columns  at  Karnak 
372     Rock  Tombs  under  the  Great  Pyramid 

at  Geezeh 
376-89     The  Two  large  Pyramids  at  Geezeh 

377  The  Colossi  of  the  Plain,  the  celebrated 

Statues  of  Memnon,  at  Thebes 

378  The    Temple    Palace   of    Goorneh,   at 

Thebes,  commenced  by  Sethos,  some 

3000  years  ago 

379-80-01     The  Memnonium  at  Thebes 
382-3-4-5-6     Medeenet   Haboo.  the   Temple 

Palace  of  Rameses  III.  at  Thebes, 

about  1300  B.C. 
387     The  Valley  of  the  Tombs  of  the  Kings, 

at  Thebes 
390-91     The  entrance  to  the  Great  Temple 

at  Luxor 
392    The  Court  of  Sheshonk  (the  Shishak  of 

the  Scriptures)  at  Karnak 

1876.    HOLY  LAND. 

400  Gaza.     The  Modern  Town 
400D  Gaza.     The  Old  Town 

401  Samson's  Gateway.     (Gaza) 
402-3     Ramleh,  the  ancient  Arimathaea 
404    Village  of  Aboo  Gosh,  Kuriat  el  Enab, 

the  ancient  Kirjath  Jearim 
405-6    Jerusalem  from  the  Mount  of  Olives 

407  Jerusalem.     Pool  of  Bethesda 

408  Jerusalem.     Church  of  St.  Anne 

439    Jerusalem,  from  the  north-east  corner 
of  the  present  city 

410  En  Rogel;    or,  the   fountain-head  of 


411  Jerusalem,  from  fortification  on  Sion 

412  Jerusalem,  from  the  south  part  of  the 

city  wall 

413  Jerusalem,  from  the  chief  tower  of  the 


414  Jerusalem.     View  from  the  south  wall 

on  Mount  Sion 

415  Jerusalem.'     View    taken   within    the 

present  city 

416  Tomb  of  Absalom,  at  the  foot  of  the 

Mount  of  Olives    , 

417  Jerusalem,  from  the  south-east 

418  Jerusalem,  from  the  top  of  the  Mount 

of  Olives 
419-20   Jerusalem,  from  the  top  of  the  Citadel 

421  Jerusalem,  English  Protestant  Church 

422  Jerusalem,  from  the  Mount  of  Olives 

423  Tomb  of  Rachel,  from  the  north-north- 


424  Bethany,  from  the  south 

425  Bethlehem,  from  the  north-east 

426  Hebron.     Southern  half  of  the  city 

427  Hebron,  the  Pool  of  David 




428  Hebron.     Northern  half  of  the  city 

429  The  Dead  Sea,  seen  from  its  northern 

shore,  looking  west-south-west 

430  Monastery  of  St.  Saba 

•      431-2-3-4     Banias,  the  ancient  Paneas  and 
Cresarea  Philippi 

435  The  Ford  of  the  Jordan,  the  site  of  the 


436  Distant  View  of  Damascus 

437  The  Old  Wall  of  Damascus 

438  Damascus.     The  East  Gate 

439  Panorama  of  Damascus,  looking  west 

440  Panorama  of  Damascus,  looking  south- 


441  Panorama  of  Damascus,  looking  east1 

442  Damascus,  Roman  gateway  and  street 


443  Nazareth,  from  the  south-east 

444  Nazareth,  from  the  north-west 

445-6     Nablous  (ancient  Sidiem  or  Sechem) 

447  Nablous,   seen    from   the    south-west ; 

Mount  Ebal  is  seen  to  the  left,  and 
Mount  Gerizim  to  the  right 
447D  Sebustieh,  the  ancient  Samaria 

448  Tiberias,  seen  from  the  south,  on  the 

shore  of  the  lake 
449-50     Baalbec,  the  ancient  Heliopolis,  or 

City  of  the  Sun.     The   Six   Great 

Columns  and  the  smaller  Temple 
451-52    Baalbec.    View  from  the  north-west 

and  the  south-east 

453  Baalbec.     The  Temple  proper 

454  Baalbec.     The  Octagon  Temple 
455-6-7    Cedars  of  Lebanon 


458  Cairo.     Group  of  Tombs  and  Citadel, 

from  the  Mukattan  Hills 

459  Cairo.      Ruined   Mosques,   with    Cufic 

writing  on  the  Mukattan  hills 
460-61-64     Cairo.     The  Mosque  of  Sultan  el 


462-65-90     Cairo  from  the  citadel 
463     Cairo.     Gateway  of  the  Ruined  Palace 

of  the  Grand  Vizier,  and  Mosque  of 

466-91     Cairo.      The   Mosques  of   Mardani 

and  Sultan  Hassan,  City  Walls  and 

General  View,  looking  south-west 
467-8     Cairo.     Modern  Painted  Tombs,  near 

Cairo, — Tombs  of    the   Caliphs    in 

the  distance 

469     Boulac.    The  Port  of  Cairo 
470-74     Cairo.     Tombs  of  the  Caliphs 
471-72    Cairo.     Street  Scene  on  the  Way  to 

the  Citadel 

473-75     Cairo.    Gateway  of  the  Citadel 
466     Cairo.     View  in  the  Roumaleah  Square, 

and  Mosque  of  Mahmoudieh,  with 


477-8-9  Belzoni's  Pyramid  at  Geezeh 
480-82-85^  The  Pyramids  of  Dashour 
481  Arab  Sportsman  and  Cook 

483  The  Pyramids  of  Sakkara 

484  The  Three  Pyramids  of  Geezeh 

485  Cairo.    The  Babel-el-Nasr,  or  Gate  of 

Victory     . 

486-7-8     Cairo.    Tombs  of  the  Mamelukes 
489     The  Mosque  of  Emeer  Akoor 

492  Cairo.     From  the   Citadel   Fort,  with 

distant  View  of  the  Tombs  of  the 

493  Cairo.     View  from  the  Citadel  Fort 

494  Camels  and  Prickly-pear  Orchard 

495  Suez,  on  the  Red  Sea 

496  Peninsula  of  Sinai.     The  Wady  Bahala 

497  Peninsula  of  Sinai.     Sculptured  Stones 

at  Sirabit-el-Rhadem 
498-9       Peninsula    of    Sinai.       The    Wady 

Mukatteb,  or  Written  Valley,  and 

Sinaitic  Inscriptions  in  this  Wady 
500-1-2-3     Peninsula    of    Sinai.      View    of 

Mount  Serbul  from  Wady  Feiran 
504-5     Peninsula   of    Sinai.     View    in    the 

Wady  Feiran 
506-7     Peninsula  of  Sinai.     The  Convent  of 

Sinai,    and    the  distant   plain    of 

508-9     Peninsula  of  Sinai.     Bird's-eye  View 

of  the  Convent  of  Mount  Sinai 
510-11     Peninsula    of   Sinai.     Mount   Sinai 

(Horeb)  with  the    Convent.     From 

the  Plain  of  El-Raheh  (the  Place  of 

the  Assemblage) 

512  Peninsula    of    Sinai.      Gebel    Mousa 

(Sinai)  from  the  Wady-es- Sebaiy eh 

513  The  Island  of  Grayia 

514  Jerusalem.     Facade  at  the  Church  of 

the  Holy  Sepulchre 

515  Jerusalem.     Street  in  Jerusalem,  with 

Church  of  the  Holy  Sepulchre 

516  Jerusalem.     The  Village  of  Siloam,  and 

Valley  of  Kidron 

517  Jerusalem.     Ancient  Tombs  in  Valley 

of  Jehoshaphat 

518  Jerusalem  from  Mount  Scopus 
519-20-21-22    Jerusalem  from  the  Mount  of 


523    Mount  of  Olives.     The  Church  of  the 
Ascension  « 

1878    A  Collection  of  Photographic  Lantern  VIEWS  of  the  most  interesting 
localities  in  the  World.    Plain,  Is.  6d.  each.    5s.  Coloured. 

45,    CORNHILL,    E.G.,    AND    122,   REGENT   STREET,    W.,    LONDON. 

1879    SCRIPTURE  SCENES.    Price  5s.  each  Coloured. 


Adam  and  Eve  in  the  Garden 

of  Eden 

The  Expulsion  from  Paradise 
Cain  and  Abel 
Adam   finding   the  body  of 

Noah  sending  the  Dove  from 

the  Ark 
Sending  away  of  Hagar  and 

Hagar  and   Ishmael   in  the 


Sacrifice  of  Isaac 
Jacob  and  Laban 
Jacob's  Dream 
Eebecca  at  the  Well 
Departure  of  Kebecca 
Arrival  of  Rebecca 
Joseph  sold  by  his  Brethren 
Joseph  interpreting  Pharaoh's 


Worship  of  the  Golden  Calf 
Pharoah's    daughter  finding 


Moses  striking  the  Rock 
The  Brazen  Serpent 
The    Angel     appearing     to 


Ruth  in  the  corn  fields 
Ruth  and  Boaz 
Samson  slaying  the  Lion 
The  Death  of  Samson 
Jael  and  Sisera 
Samuel  and  Eli 
Samuel  praying 
Saul  and  the  Witch  of  Endor 

David    with    the    Head    of 


The  Judgment  of  Solomon 
Mordecai's  Triumph 
Daniel  in  the  Den  of  Lions 
The  Handwriting  on  the  Wall 
Job  and  his  Three  Friends 
The  Angels  appearing  to  the 

The  Nativity 

The  Adoration  of  the  Magi 
The  Flight  into  Egypt 
The  Murder  of  the  Innocents 
Christ  with  the  Doctors  in 

the  Temple 
The  Holy  Family 
The  Baptism  of  Christ 
Christ  at  the  Well  with  the 

Woman  of  Samaria 
Christ    giving   sight  to  the 


Christ  healing  the  Sick 
Christ  blessing  Little  Child- 
The  Miracle  at  the  Marriage 

Feast  at  Cana 

Christ  and  the  Tribute  Money 
Christ  weeping  over  Jerusa- 

Christ's  entry  into  Jerusalem 
Mary  anointing  Jesus's  feet 
Christ  raising  Lazarus 
The  Miraculous   Draught  of 

Christ  walking  on  the  Sea 


The  Prodigal  Son  in  want 
The  Return  of  the  Prodigal 


The  Good  Shepherd 
The    Vineyard— Hiring    the 

The   Husbandman    and    the 


The  Unjust  Steward 
Dives  the  Rich  Man 
The  Wise  &  Foolish  Virgins 
The  Good  Samaritan 
The  Widow's  Mite 

Christ's  Agony  in  the  Garden 

The  Last  Supper 

Christ  before  Pilate 

Ecce  Homo 

The  Crown  of  Thorns 

Christ  bearing  His  Cross 

The  Crucifixion 

The  Dead  Christ 

The  Descent  from  the  Cross 

Mary  at  the  Sepulchre 

The  Ascensiom 

Stoning  of  Stephen 

The   Angel    releasing 

from  Prison 
Death  of  Ananias 
Conversion  of  St.  Paul 
Paul  Preaching  at  Athens 
Elymas  struck  Blind 
Sacrificing  before  Paul 




Rice  Sellers 
Cat  Merchants 
Chinese  Punishments 
Opium  Smokers 
Chinese  Jugglers 
Feast  of  Lanterns 
Chinese  Junk 
Shuttlecock  playing  with  the 


Travelling  Tinker 
The  Great  Wall 
Chinese  Lantern  Maker 
Temple  of  Buddha,  Canton 
Chinese   Ladies    Playing 


Chinese  Ladies'  Boudoir 
Panorama  of  Canton 


Panorama  of  London 
The  Marble  Arch 
Buckingham  Palace 
Westminster  Abbey 
Houses  of  Parliament 
Victoria  Tower 
Clock  Tower 
The  Horse  Guards 
Trafalgar  Square 
tSt.  Martin's  Church 



Transplanting  Rice 
Chinese  Boatmen 
Ditto    ditto  fighting  Quails 
Chinese  Dice  Players 
Chinese  Emperor  Reviewing 

his  Guards 

Silk  Farm  at  Hoo  Chow 
Winding  the  Cocoons 
Feeding    Silk     Worms     and 

sorting  Cocoons 
Chinese  Temple 
Chinese  Joss  House 
Bridal  Presents 
Chinese  Capmaker's  Shop 
Bamboo  Aqueduct  at  Hong 

Loading  Tea  Junks 

London.    Plain  2s.  Coloured  5s.  each. 

Coloured.  5s.'each. 

Pavilion   and   Gardens  of  a 

Culture  of  Tea 
Celebration  of    Meeting  the 

Kite  Flying  on  the  9th  day 

of  the  9th  moon 
An  Itinerant  Doctor 
Ditto      Barber 
Raree  Show 
A  Street  in  Canton 
Western  Gate,  Pekin 
The  Nine-storied  Pagoda 
The  Five-storied  ditto 
The  Hall  of  Audience,  Pckiu 

The  British  Museum 
Temple  Bar 
Waterloo  Bridge 
Somerset  House 
St.  Paul's 
The  Post  Office 
The  Bank 
The  Royal  Exchange 

The  Monument 
London  Bridge 
The  Custom  House 
The  Tower 
The  Royal  Mint 
The  Trinity  House 
St.  Katherine's  Docks 
Victoria    and    Albert 



1882  Crystal  Palace.     Comprising  all  the  Courts  and  objects  of  interest. 

1883  Java,   Sumatra,   Japan,   Siam,   Manilla,  Moluccas;   a  series  illustrating 

Tropical  Scenery. 

1884  Prepared  Colours  for  Painting  on  Glass,  12  Colours,  with  Brushes,  Palette 

Knife,  Yarnish  and  Turpentine,  in  neat  japanned  tin  case,  24s.  and  42s. 

1885  Single  Colours  for  Painting  on  Glass,  Is.,  Is.  6d.,  and  2s.  each. 

1886  Varnish,  prepared  for  ditto,  Is.  6d.  per  bottle 

These  Lists  comprise  only  a  very  small  portion  of  Negretti  and  Zambra's  Photographic  Series  that 
can  be  conveniently  described  within  the  limits  of  a  Catalogue. 

Engraving*,  Drawings,  Maps,  &c.,  copied  by  Photography  for  Projection 

by  the  Lantern. 

Instructions  for  Painting  Lantern  Slides  will  be  found  at  page  94  in  N.  &  Z.'s 

Lantern  Manual. 

FIG.  1887. 

The  wood  engraving  (fig.  1887),  exhibits  in  section  the  general  arrangements 
of  the  improved  3  Wick  Parrafin  Lanterns.  P  and  Q  are  the  Condensing  Lenses, 
A,  B,  and  C  the  Achromatic  Combination  of  Front  Lenses,  having  Hackwork 
Adjustment,  S,  U,  Y,  the  Lamp,  I  and  J  Chimney  and  Cap,  O  O  Spring  Clamp 
for  holding  the  picture,  G,  Flame  Chamber  Glasses,  B,  Reflector  closing  down  on 
the  back  of  the  Lamp  Chamber.  The  Slide  Holder  is  open  at  the  top  and  is 
adjustable,  admitting  of  a  variety  of  chemical  and  other  experiments  being  performed 
and  exhibited  upon  the  screen. 

45,  CORNHILL,   B.C.,   AND   122,   EEGENT  STEEET,   W.,   LONDOX. 



FIG.  1888. 








£     s.     d.         £     s.     d. 
Adapters  for  connecting  retorts  to  receiver,  small  tube, 

straight,  8  oz.  and  16  oz 009        0     0  10 

Ditto        ditto,  bent,  8  oz.  and  16  oz 0    0  10        010 

Adapters,  full  size,  for  large  operations    .         .   various 
Air  Jar  Tubes,  for  experiments  on  the  gases  : — 

Long    .    2-in.  3-in.  4-in.  6-in.  6-in. 

Width.    -1-in.  |-in.  |-in.  f-in.  1-iu. 

Price       .    3d.  4d.  6d.  94  lOd. 

Air  Jar  Tubes,  Cylindrical,  per  nest  of  six      .         .        .086        0  10     6 
Air  or  Gas  Jars,  stout  bell  glass,  with  ground  edges — 

£-  pts.  pts.      qts.  3  pts.          4  pts. 

Narrow  Mouth,  plain  (fig.  t)  Is.  3d.       2s.      3s.        4s.  6d.        6s. 

$-pts.  pts.  qts.  3  pts. 

Air  or  Gas  Jars,  Stoppered  (t)  2s.          3s.  4s.         5s. 

Ditto  ditto  mounted  with  Brass  Cap  2s.  6d.    3s.  6d.      5s.  6d. 

6s.  6d. 


Air  or  Gas  Jars,  Wide  Mouth,  Plain    Is.  6d.    2s.  6d.    .    4s. 

Ditto,        ditto  Stoppered    2s.  6d.    3s.  6d.        5s.        6s. 

Air  or  Gas  Jars,  mounted  with  Brass  cap,  two  Stop- 
cocks, Connecting-piece,  and  Bladder  Ferrule  from 

Air  or  Gas  Jars,  Graduated  into  Cubic  Inches  and 
Decimal  parts,  for  mixing  gases,  Capped  or  Stoppered  from 

4  pts. 


8s.  6d. 
7s.  6d. 
8s.  6d. 

0  18    0 







FIG.  1902. 

FIG.  1903. 

FIG.  1904. 






FIG.  1907. 


FIG.  1907*. 

Alkalimeters  or  Chlorimeters,  Sink's  form  (fig. 

Ditto        ditto,  with  Foot  (fig.  1903)        .... 

Ditto        Gay  Lussac's  (fig.  1904) 

Ditto         old  form  .         . 

Schuster's  Alkalimeter  (fig.  1906) 

Alkalimeter,  1000  grains,  divided  into  100  parts  of 
equal  capacity,  for  Volumetric  Analysis  (figs.  1907 
and  1907*) 0 

Alembics — 

4  oz.  8  oz.  16  oz. 

Earthenware        .        .        .2s.  6d.      3s.  6d.    4s.  6d.    ( 
Glass  (fig.  1908)    .        .        .6s.  6d.      7s.  6d.     12s. 

Alembics  of  German  Glass,  4  oz.  and  6  oz.  capacity,  for 
experimental  distillations 

Alembics,  Berlin  ware,  with  movable  head,  for  distil- 
lation of  substances  at  very  high  temperatures  . 

Arsenic  Tubes,  of  hard  German  Glass,  Berzelius', 
Clark's,  Liebig's,  or  Rose's  form  (fig.  1911)  per  doz. 

Aspirators,  Glass,  see  Water  Bottles. 

Barometer  Standard,  for  Laboratory  use,  entirely  of 
Glass,  Gay  Lussac's  syphon  form,  the  scale  divided 
on  the  tube  either  inches  or  millimetres 


66        086 


6s.  6d. 

0  12  6 

330        550 

See  ante,  page  11. 

Basins,  Evaporating,  of  Berlin  ware,  flat  bottoms, 
with  spout,  shallow  form;  depth,  one-fourth  the 
diameter : — 

Contents    .       1-oz.       2-oz.       3|-oz.        5-oz.       8-oz.       12-oz.        T8-oz. 

Price          .      9d.      lOd.        Is.     Is.  3d.  Is.  6d.     2s.      2s.  6d. 
Basins,  Berlin  Porcelain,  small  and  thin,  for  Analytical 
Experiments,  uniform  in  substance  : — 

Contents    .       g-oz.  i-oz.  f-oz.  1-oz.  H-oz.  2-oz. 

Price  3d.          5d.         6d.          8d.          lOd.         Is. 

45,   CORNHILL   E.G.,   AND    122,    REGENT    STREET,   W.,   LONDON. 








FIG. 1908. 

FIG.  1911. 

FIG. 1906. 

FIG.  1918. 

Beaker  Glasses,  (fig.  1916),  Cylindrical  form,  the  glass 
uniformly  thin  and  well  annealed,  of  German  manu- 
facture; Sets  of 3  5  8  12 

Price 2s.        3s.      5s.  6d.  11s.  6d. 

Beaker  Tumblers,  with  spout,  for  hot  solutions,  &c.,  being  shorter, 

are  easier  cleaned  than  beakers,  and  precipitates  more  easily     £    s. 
removed.     In  sets  of  six  (fig  1917) 06 

Bottles,  best  Flint  glass,  London  Stoppered  (fig.  1918) : — 

i-oz.,  ^-oz.,  and  1  oz.,  narrow  mouth,  per  doz.  4s.  wide  mouth  per  doz.  0 
2-oz.        ...  „  „        5s. 

3-oz.        ....  „  „        6s. 

4-oz.        ...  -  „  „        7s. 

6-oz.        .  „  „        8s. 

8-oz.  ... 
10-oz.  ... 
16-oz.  „  ,  „ 

20-oz.        ... 

Bottles,  Green  glass,  Stoppered  : — 

i-pint,  narrow  mouth,  per  doz.  5s.       wide  mouth,  per  doz. 
i-pint   -  ,  „        5s.  6d.        „ 

1-pint  „  „        6s.          ,     „  „ 

2-pint  „  7s.  „  „ 

Bottles,  Acid,  with  elongated  stoppers      ....         from 

Ditto,  Capped,  for  uEther,  &c.  i-oz.  2-oz.  4-oz. 

2s.  2s.  6d.  3s. 

Ditto,  Capped,  and  fitted  into  turned  wood  boxes,  various,  from 

Bottles,  small  Tube,  for  containing  rare  specimens,  plain,  per  doz. 

Ditto        ditto,  Stoppered 

Bottles,  Specific  Gravity,  Grains  or  Grammes,  see  Specific  Gravity. 

os.         „ 

9s.  6d.  „ 

10s.  6d.  „ 

11s.  6d.  „ 

13s.  6d.  „ 

0    5 


0    6 


0    7 


0    8 


0    9 


0  10 


0  11 


0  13 


0  15 





3s.  6d. 



FIG.  1926. 

FIG.  1948.        FIG.  1946. 

FIG.  1969*. 

FIG.  1932. 



1926  Bottles,  washing,  Gmelin's  (fig.  1926)         .... 

1927  Ditto        ditto,  with  Handle  for  hot  water,  &c 

1928  Capsules,  glass 003 

1929  Capsules,  of  Berlin  Porcelain,  with  spout  and  handle,  very  light : — 

Contents    ....  1-oz.  2i-oz. 

Price lOd. 

1930  Bulb  Tubes  for  weighing  Oxide  of  copper  '  .  each 

1931  Brunner's  Aspirator,  consisting  of  a  Glass  Bottle,  one 

gallon  capacity,  with  tap 

.  For  other  sizes  of  this  useful  article,  see  Water  Bottles. 

1932  Connecting  Tubes,  Bent  (fig  1932)         .        .         each 

1933  Combustion    Tube    of    Hard    German    Glass,    very 

infusible per  Ib. 

1934  Combustion  Tubes  prepared  from    the  above  Glass 

per  doz. 

1935  Chloride  of  Calcium   Tubes,   for    absorbing  moisture 

from  gases,  with  straight  or  bent  point  (figs.  1935)  each 

1936  Ditto        ditto    U  shaped,  with  two  bulbs  (fig.  1936)    . 

1937  Crucibles,  real  Hessian,  triangular  shape,  in  nests : — 

Nest  of  3  Crucibles,  Nos.  2  to  4 

5  1  to  5 

6  1  to  6 

,,8  1  to  8  .  ... 



Is.  2d. 


0  10  0 

'0  0  6 


45,    COENHILL,    E.G.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


1938    Crucibles,  London  Made,  Fire-Clay,  round  form,  capable 

of  resisting  high  temperatures  : — 
Height,  without  covers      3-in.  4-in.          4|-in.         5-in.          6-in.         7-in. 

Price  ;        .      2d.        2R        3d.        4d.        5d.        8d. 

Covers  at  the  same  prices  as  the  Crucibles. 














1  : 

















•  - 



3>  1948 

Crucible    Cases,    or  Jackets    and  Covers,  of  fire-clay,   to 
protect  platinum  crucibles,  and  raise   them   to  where  the 

heat  is  the  most  intense 
Crucibles,  Wedgwood  Ware  . 
Ditto,  Skittle  shape  3  to  12  inches  high, 

from     ....... 

*Ditto,  Bound,  with  Covers  . 

Ditto,  Berlin  Porcelain,  various      from 

Ditto  ditto,  not  glazed,  with  perforated 


Calcining  Pots,  to  open  in  the  middle    . 
Cooper's  Receiver,  for  collecting  Gases 

over  mercury  (fig.  1946) 
Ditto  ditto,  Graduated   . 
Cryophorous,    Wollaston's,    or   Frost 

Carrier  or  "Rearer  (fig.  1948) 

Cubic  Inch  Tubes,  graduated  into  lOths  and  lOOths 
(fig.  1949) 

1950  Ditto        ditto        on  Round  Foot  (fig.  1950) 

1951  Cubic  Inch  Bottles,  (see  Specific  Gravity  Bottles). 






























FIG.  1949.  FIG.  1950. 


FIG.  1961. 

FIG.  1963. 

FIG.  1952. 


Drying     Tube,    (fig.    1729)    a    bent    tube   in   which 

substances  to  be  analysed  are  placed  to  dry  them,  each 





Drainers  for  Crystals,  Porcelain     





Ditto        ditto        shallow  form      





Deflagrating  Jars,  (see  Gas  Receivers)   .... 


Dishes,  Glass,  various  shapes          .         .         .          from 





Ditto,  Evaporating,  Berlin  ware,  various. 


Dishes,  Evaporating,  Wedgwood  ware,  not  liable  to  stain  or 

crack  :  — 

Diameter  .    2-in.            3-in.               4-in.         5-in.          6-in. 


Price             .    4d.          6d.            9d.        Is.       Is.  4d. 

Is.  8d. 

Diameter  .           .     8-in.                  9-in.             10-in.        11-in. 


Price    .         .         .2s.             2s.  6d.        3s.       3s.  9s. 

4s.  6d. 


Dishes,  Sulphuric  Acid,  for  desiccating  purposes  . 





Ditto,  Washing,  flat  Porcelain  (see  Photographic  Apparatus). 


Dropping  Tubes,  or  Pipettes  (fig.  1961)       4d.,  6d.,  and 





Ditto        ditto        Graduated  to  grains,  &c.           .         .     0 

3    0 





Dropping  Bottles  (as  fig.  1963)      0 

2    0 





Dialysers,  Graham's  Glass,  with  Welt  top  and  bottom  Is.  0 

1    6 







FIG.  1978. 

1965     Desiccating  Jars,  for  drying  gases  by  the  aid  of  Chloride 
of  Calcium  (fig.  1965)   ....... 

1967  Desiccating  Tubes,  with  one  bulb,  and  the  end  straight 

or  bent  (fig.  1935) 

1968  Evaporating  Dishes  (see  Dishes). 

1969  Ettling's  Gas  Transferors,  various  forms  (figs.  1969, 1969*) 

1970  Eudiometer,    Volta's,   graduated    to  200  divisions=2 

Cubic  Inches  (figs.  1970  and  1970*)  .     ( 

1971  Eudiometer,  Ure's  U-shape  (fig.  1971),  graduated  to 

200  divisions=2  Cubic  Inches     ..... 

1972  Flasks,  Florence 

1973  Flasks,  White  Flint  Glass  wide  and  narrow  mouthed, 

with  round  and  flat  bottoms,  from  1-oz.  to  1-qt.,  from 

1974  Flasks,  with  Side  Neck,  for  Fractional  Distillation, 

(fig.  1974)      ....      1  pint,  2s.  6d.  2  pints, 

1975  Flasks,  very  light,  mounted  with  Brass  Stop-Cock  for 

weighing  gases      ........ 

1976  Flasks,  Graduated  to  hold  1  Pint  Imperial   . 

1977  Flasks,  Graduated  to  hold  exact  quantities — Grains, 

Cubic  Inches,  or  Cubic  Centimetres    .... 




d.         £ 

s.     d. 


6        0 

11    0 

0    6 


3    6 


6        0 

12    6 


10    6 
0    4 


4  to  0 

4    0 


5    0 



12    6 
3    6 


6        0 

5    6 

FIGS.  1974,     1978*. 

Flasks  of  Hard  German  Glass,  capable  of  resisting  extreme  and  sudden 
changes  of  temperature ;  flat  or  round  bottoms  (figs.  1978  and  1978*) : — 














Is.  3d. 


Is.  6d. 



1979    Filter  and  Funnel  Rings  of  Porcelain  (fig.  1979)  4d.  and  6d. 

45,    CORNHILL,   E.G.,   AND    122,   REGENT   STREET,   W.,   LONDON. 
FIG.  1980.  FIG.  1985.  FIG.  1984. 


FIG.  1984.  FIG.  1982.       FIG.  1983.     FIG.  1983*. 

1980  Funnels,  of  Glass  (fig.  1980)  :— 

Diameter    .    1J  in.        U  in.        2  in.         2£  in.         3  in.         4  in.  5  in.         6  in. 

Price  3d.        4d.        5d.        6d.        8d.        Is.      Is.  6d.      2s. 

1981  Funnels,  "Wedgwood  ware,  best  quality,  from  2-oz.  to  2-qts.    from    £009 

FIGS.  1993.  and  1993*.  FIG.  1994.        FIG.  1995.        FIG.  1990. 

1982    Funnels,  long  tube,  thistle-headed  for  gas  bottles,  &c. 
of  blown  glass  (1982)  :— 

Length  .  4  in.        13  in.         18  in.       20  in.  24  in. 

Price      .        4d.         6d.        9d.         Is.         Is.  3d. 
1933     Funnels,  for  filling  plain  Retorts  without  soiling  the  neck 

(figs.  1983  and  1983*) £026 

1984  Funnels,  with  Handle,  for  introducing  substances  into 

tubes  without  soiling  the  sides  (fig.  1984)   .        .        .£026        036 

1985  Ditto  with  Stopper  (fig.  1985) 046 

1986  Ditto  with  Glass  Stop-Cock  (fig.  1986)  .        ...  0  12    6 





FIG.  2017.    FIG.  1979 

FIG.  1970.     FIG.  1971.  FIG.  1970*.  FIG.  1998. 

1989  Gas  B  ottle,  Clark's,  for  preparing  Sulphuretted  Hydrogen, 

1990  Gas    Bottle,    with    bent    glass    tube,    for    generating 

Hydrogen,  Sulphuretted   Hydrogen,  Carbonic  Acid, 
or  Chlorine  Gases  (fig.  1990)  .         .         .          complete 

10  oz.  16  oz.  20  oz.  40  oz. 

Price        .        .     Is.  6d.          2s.  2s.  6d.  3s. 

1991  Gas  Flasks  with  Bent  tubes  as  fig.  1763 

1992  Oxygen  Gas  Retort,  of  hard  glass,  with  bent  tube,  for 

making  pure  Oxygen  from  Chlorate  of  Potash  and 
Oxide  of  Manganese     ....... 

1993  Gas    Receivers  or  Deflagrating   Jars   (figs.  1993  and 

1993*)    for    containing    and    preserving    Gases     for 
experiment  : 


.    3  in.     . 
.     4  in.     . 

s.    a. 

2    6 



Price  Plain. 


Is.  9d. 

2s.  6d. 
4s.  6d. 

Price  Stoppered. 

Is.  6d. 



7s.  6d. 


5  in.     . 

7  in.     . 

94  in.  .         .    5i  in. 

Hi  in.         .    6i  in. 

1994  Gas    Receivers    mounted    with    brass    cap,    stop-cock 

and  bladder  ferrule,  (fig.  1994) 

about  7  in.  high   .         .         .     4  in,  wide 
„      9  in.     ,,       .         .         .5  in.     „ 

1995  Gas  Receiver  (fig.  1995),  mounted  with  Brass  Cap  and 

Stop-cock,  and  Graduated  into  Cubic  Inches 

1996  Globular  Receiver,  with  welted  mouth,  for  showing  the 

combustion  of  Phosphorous,  &c.,  in  Oxygen  Gas 

1997  Gas  Jars,  Cylindrical,  Stout  Glass,  for  exhibiting  the 

explosive  nature  of  a  mixture  of  Oxygen  and  Hydrogen 


0  10    6 
0  12    6 

0  16    6 


009      010 



FIG.  2028. 

FIG.  2098. 

FIG.  2029.  FIG.  2028*.  FIG.  2099.  FIG.  2099* 

1998    Graduated  Gas  Tubes,  for  measuring  Gases,  &c., 
(figs.  1998  and  1998*)  :— 
4  in.  |  in.  about  1  cubic  inch,  showing  l-100ths  cubic  inch 

6  in.  |  in.      „      1  „        1-lOOtha 

7  in.  f  in.      „      3  cubic  inches   „        l-50fchs  „ 
10  in.  1  in.      „      1          „                „        l-10ths 
12iin.l|in.  „    14          „                „         l-10ths 






Dumas's  Gas  Tubes,  for  Nitrogen  determinations,  17  in. 
by  1£  in.,  containing  about  20  cubic  inches,  and 
divided  to  either  l-10th  of  a  cubic  inch  or  cubic 
centimetres  ......... 

Liebig's  Gas  Absorber,  for  saturating  a  liquid  with  Gas, 
and  useful  in  preparing  a  solution  of  any  gas 

Kerr's  Gas  Tube,  stoppered  and  graduated  to  2  cubic 
inches,  so  as  to  show  l-10fch  of  a  cubic  inch  (fig.  2001) 

Glass  Plates,  ground,  for  covering  Air  Jars  :— 

Square     .        2in.  2£  in.  3  in.  4  in.  8  in. 

Price        .        8d.          lOd.  Is.        Is.  6d.         2s. 

German  Glass  Tubing,  free  from  lead,  in  lengths  of 

about  36  or  18  inches,  for  convenience  of  packing  :  — 

£  in.  bore  and  under      ....        per  Ib. 

n.       n. 

down  to     in. 

£     s.     d. 

4  6 

5  6 

0  12    6 



FIG.  2001, 

FIG.  2012. 

FIG.  2012*. 










FIG.  2016.       ,  FIG.  2014*. 

FIG.  2014. 

FIG.  2015. 

FIG.  2015* 

£    a.    d. 


0  15    0 





Flint  Glass  Tubing,  very  soft,  easily  bent  and  worked  : — 
i  in.  bore  and  under  ....  per  Ib. 
1  in.  ^in,  „  down  to  ^in.  .  .  ,, 

Combustion  Tube,  German  Glass  „ 

Gauge    Tube,   for    Steam    Boilers,    &c.,    according    to 

diameter,  see  page  197 per  inch 

Glass  Rod,  of  various  diameters      .         .         .      per  Ib. 

Glass  Inhalers 

Lamp,  Hydrogen,  Dobereiner's        .        .        .    10s.  6d. 
Lamps,  Spirit,  glass,  round  tops  and  Brass  mounts, 

(figs.  2010  and  2010*)    .        .        .        .        .      2s.,  3s. 

Ditto  ditto,  Common  Mountings 

Lixiviating  Jars  (figs.  2012  and  2012*)  of  German  Glass 

strong  and  convenient  in  shape,  for  cold  fluids : — 
Contents  .  1  pt.  H  pt.  2  pts.  3  pts. 

Price  .  .  Is.  Is.  4d.  2s.  2s.  9d. 

Liebig's  Retort,  with  extra  neck  for  passing  gases  over 

any  substance  while  heated  for  distillation,  best  hard 

Bohemian  glass  (fig.  2013) 

Measures,  Graduated  Glass,  showing  ounces  and  drachms 

(figs.  2014  and  2014*) :— 

Conical  or  Cylindrical  Form        1-oz.  2-oz.  4-oz.      .         8-oz. 

Price      .        .        Is.          Is.  2d.  Is.  9d.        2s. 

Measures,  Glass,  Graduated  Imperial  Pint  (fig.  2015)  036 

Ditto  ditto  ditto        Quart  (fig.  2016)  050 

Measures  divided  to  show  equal  parts,  Grains,  Cubic  Inches,  or  Centimetres 
&c.,  to  order  (fig  2017).    Price  various. 


0    5 



2s.  6d. 

FIG.  2013. 

FIG.  2030. 

45,    CORNHILL,   E.G.,  AND    122,    EKGENT    STRKET,    W.,    LONDON. 


FIG.  2034*. 


£    s.    d. 

at     s.       u 

2018  Measures,  Glass,  one  drachm,  divided  into  drop  or  60 

minims  (fig.  2014*) 012 

2019  Ditto,  Cubic  Inch  divided  into  lOths  (fig.  1950)    .         .  056 

2020  Mercurial  Trough,  Porcelain  (fig.  2030)                  from  026        05-6 

2021  Mortars  and  Pestles,  Agate. 

The  prices  are  only  approximate,  as  they  vary  according 
to  the  soundness  of  the  materials,  as  well  as  size  : — 

Diameter        If-in.        If-in.  2-in.  2|-in.  2|-in.  3-in.  4-in.  6-in. 

Price        8s.  6d.        9s.         10s.         12s.         15s.        20s.        55s.        60s. 

2022  Mortars  and  Pestles,  Berlin  porcelain  .  Is.  6d.,  2s.  6d.,    036        056 

2023  Mortars  and  Pestles,  best  quality,  "Wedgwood  ware  :  — 

Diameter       2|-in.  2i-in.  3-in.  3J-in.  3|-in.  4J-in.  6Hn. 

Price  Is.          Is.  4d.     Is.  6d.       2s.  2s.        2s.  6d.          5s. 

2024  Ditto,  in  Stout  Glass        .   2s.  6d.        3s.  Od.        3s.  6d.    0    4    6        066 

2025  Mineralogical  Anvils,  Hard  steel,  small  square      .        .076        0  10    (3 

2  c 



FIG.  2035. 








£    s.  d. 

1    6 
1    0 

FIG.  2035*. 

Muffles .    9d.    Is     0 

Mixing  Jars  for  Alcalimetry  (figs.  2027  and  2027*)       .    0 
Test  Mixers  (fig.  2028,2028°),  for  preparing  Test  Acid; 

containing  1,000  septems,  divided  into  100  divisions  . 
Parting  Glasses,  for  assaying  (fig.  2029)  .  .  from 
Pneumatic  Trough,  mercurial,  Berlin  ware,  for  tube 

experiments  (fig.  2030°) 

Porcelain  Retort,   (Berlin)   tubulated  and  stoppered, 

contents  about  forty  fluid  ounces  (fig.  2030) 
Pipettes,  with  Round  or  Pear  shaped  bulbs  (figs.  2032 

and  2032*)     ....  ....    0    0    6 

Pipettes,  or  Dropping  Tubes,  straight  bulb,  6-in.  long      006 
Ditto,  with  elongated  bulb,  for  use  in  Edulcoration 

(figs.  2034  and  2034*) 

Pipettes,  Graduated,  for  delivering  exactly  1,000,  700, 

500,  350,  or  50    Grains,  Cubic   Centimetres,  Equal 

Parts,  or  any  quantity  to  order 

(figs.  2035  and  2035*),  2s.  6d.  3s.  6d.,  5s.  6d.  0    7    6 
Pipettes,  with  two  bulbs,  for  delivering  exactly  500  and 

1,000  grains  (fig.  2036) 

FIG.  2037. 

2037  Pipettes,  for  passing  a  Solution  of  Potash  into  a  Gas 
contained  in  a  Tube  over  mercury  (figs.  2037  and  2037°) 

£  a.  d. 



0  13  6 



0  10  6 



FIG.  2052.  FlG.  2054.  FIG.  2052* 

2038  RETORTS,  Glass,  various  forms  and  sizes,  see  also  next  page. 

45,    COIINUILL,    E.G.,    AND    122,    REGENT   STREET,    W.,    LONDON. 


FIG.  2053. 

FIG.  2037*. 

FIG.  2040. 

FIG.  2055. 

FIG.  2041. 

£    s.    d. 



0    5 



£      s.    d. 

008        01 



010        016 

2039  Pipettes,  with  bent  points  (figs.  2039  and  2039°) 

2040  Percolator  Glass,  for  preparing  tinctures,  &c.  (fig.  2040)  1  15    0 

2041  Pourettes  or  Burettes,  divided  into  Grains,  Grammes, 

Equal  Parts  or  Cubic  measures  (fig.  2041)          .        .056        076 


2042  Precipitating  Glasses,  on  foot  (fig.  2027)   1/6 

2043  Ditto  ditto  Philip's    /7     /8    /9 

2044  Pulse  Tubes    ......... 

2045  Reduction  Tubes,  12-in.  tube,  1  or  2  bulbs,  straight  o 

bent       .......... 

2046  Reduction  Tubes,  with  one  bulb,  the  tube  bent,  for  de- 

composing oxide  of  copper  by  heat,  in  hydrogen  gas  (fig  .  2046) 

2047  Retorts,  Earthenware,  plain    .         .         .         .        .         .016 

2048  Retorts,  Earthenware,  to  open  in  the  middle        2s.  6d.     0    3     0 

2049  Ditto,  of  hard  glazed  Stoneware,  for  Acids     .          from 

2050  Ditto,  of  Berlin  Porcelain,  for  high  temperatures,  plain    046 

2051  Retort,  Porcelain,  Stoppered  ......  0  10 

2052  Retorts  of  hard  German  glass  (figs.  2052  and  2052*)  :— 

Contents        2-oz.        4-oz.        6-oz.        8-oz.        12-oz.        1-lb.        li-lb.        2-lb. 

Plain        .     4d.  4d.      6d.       8d.        9d.       lOd.      Is.      Is.  6d. 

Tubulated     7d.  8d.     lOd.      Is.     Is.  2d.  Is.  3d.  Is.  6d.     2s.    2s.  6d. 

Stoppered  Is.    Is.  4d.  Is.  6d.     2s.     2s.  3d.  2s.  6d.     3s.   3s.  6d. 

2053  Retorts  (Small)  of  blown  Glass,  2  to  4-oz.  capacity, 

plain  and  stoppered  (fig.  2053  and  2053*)     .        .        .009        01 

2054  Ditto        ditto,  with  bent  point  (fig.  2054)     ...  01 










FIG.  2059. 

FIG.  2062. 

Retort  and  Receiver,  Clark's  (fig.  2055),  exceedingly 
useful  in  small  distillation 

Receivers,  of  blown  glass,  1-oz.  to  2-oz.  capacity,  plain 
and  tubulated  (fig.  2056) 6d. 

Receivers,  Plain,  bolt  heads,  short  neck  (fig.  2057) ; — 

Contents      .         4-oz.  8-oz.  12-oz. 

Price    .        .        6d.  8d.  9d. 

Contents      .         1-lb.  H-lb.  2-lb.  3-lb. 

Price     .        .        Is.          Is.  2d.        Is.  6d.         2s. 
Receivers,  with  long  neck  (fig.  2058) : — 

Contents      .         1-lb.  H-lb.  2-lb.  3-lb. 

Price     .        .         Is.          Is.  2d.        Is.  6d.         2s. 
Ditto,  with  Tubulure  Stoppered,  the  neck  short  (fig.2059):— 

Contents      .          4-oz.  8-oz.  1-lb.  2-lb. 

Price    .        .        8d.  lOd.        Is.  2d.      Is.  lOd. 

Receivers,  with  Tubulure  Stoppered,  the  neck  long 
(fig.  2060):- 

Contents      .          4-oz.  8-oz.  1-lb.  2-lb. 

Price     .        .     Is.  2d.        Is.  4d.      Is.  lOd.      2s.  6d. 
Receivers  for  preparing  Nitric  Acid  (fig.  2061) 
Receivers  with  three  necks  (fig.  2062)          .        .        .    0 

£     s.    (1. 





FIG.  2056. 

FIG.  2027. 

FIG.  2030*. 

FIG. 2027* 

45,  CORNHILL,  B.C.,  AND  122,  REGENT  STREET,  W.,  LONDON. 


FIGS.  2068. 


FIG.  2070. 

FIG.  2067. 

£      s.    d. 

2063  Receivers,    V    shaped,    small  size,  of    German   glass 

(fig.  2063) 0 

2064  Ditto,  U  shaped,  large  size,  of  German  glass         .        .    0 

2065  Receivers,  with  delivery  tube  (fig.  2065),  for  distilling 

small  portions  of  substances  that  require  the  receiver 
to  be  surrounded  by  ice 

2066  Ditto        ditto        fitted  to  a  japanned  copper  vessel    . 

2067  Funnel,  with  bent  tube  for  charging  retorts  (fig.  2067) 

2068  Safety  Funnels  (Welter's),  for  gas  bottles,  retorts,  &c., 

various  forms  (figs.  2068)      ...... 

2069  Ditto,  with  four  bulbs,   preventing  any  fluid  in  the 

funnel  reaching  the  retort  by  sudden  condensation 
(fig.  2069) 

2070  Safety  Funnel,  with  two  valves  which  obviate  the  neces- 

sity of  using  mercury  or  fluid  in  the  funnel  (fig.  2070) 

FIG.  2069 

£    s.    d. 

0    1     3 

0  10  G 

016        026 



FIG.  2072. 

FIG.  2073. 

FIG.  2073' 



2071  Separating  Funnel,  with  Stop- Cock  and  Glass  Cover 

(fig.  2071) 

2072  Separating  or  Florentine  Keceivers  (fig.  2072) 

2073  Ditto  (figs.  2073  and  2073*)  with  Stop-Cock  and  Stopper 

2074  Specific  Gravity  Bottles,  of  1,000  grains  capacity,  with 

adjustable  counterpoise,  in  japanned  tin  case     . 

2075  Ditto,  of  500  grains 

2076  Ditto,  of  250  grains 

2077  Ditto,  1  cubic  inch 

FIG.  2063. 

£     s.     d. 

£     s.     d. 










0  16 

0  18 

0  10 


FIG.  2091. 

FIG.  2234. 

FIG.  2078*. 


FIG.  2065. 

Spirit    Lamps    of    Glass,    with     ground    caps 
Brass  wick-holders  (figs.  2078  and  2078°)  :— 

Contents    .  2-oz.  4-oz.  8-oz. 

Price   .        .  2s.  3s.  5s. 

If  with  screw  wick  holders,  6d.  extra. 

Spoons,  stout  glass,  for  transferring  small  quantities  of 
acid,  &c.,  from  one  vessel  to  another  .... 

Stirrers,  of  soft  glass,  that  do  not  scratch  glass  vessels 
in  which^they  are  used  : — 

Length  .  4-in.  6-iiu  9-in.  12-in. 

Price  (per  doz.)      .          Is.       Is.  3d.     2s.  6d.        3s. 
Stirrers,  unprepared,  in  lengths  of  18  or  24-in.  per  Ib.  . 
Stone  Ware  Still  and  Worm,  hard  glazed,  from  1  gall. 
Stone  Ware  Adapters  and  Taps,  Acid  Jugs,  Ladles, 

Funnels,   Bottles,   Pots,    Evaporating    Dishes,   and 

Coolers,  &c.,  of  various  sizes  and  shapes 

Stop -Cocks,  solid  Glass,  accurately  fitted,  the  open  end 

straight  and  adapted  to  receive  a  tube  fitted  with  cork 
Ditto,  with  Bent  End,  for  running  off  a  liquid 
Sulphuric  Acid  Dish,  for  desiccating  purposes 
Sulphuretted  Hydrogen  Gas  Bottle  (fig.  2087) 
Suction  Tube  (fig.  2088),  for  filling  Potash  Apparatus 

and  to  ascertain  if  the  connections  are  Air  Tight 

Syphon  of  a  simple  form 

Ditto,  with  Suction  Tube  ffi^s.  2090  and  2090*)     . 


026        056 

45,   COENHILL,    B.C.,    AND    122,    EEGENT    STREET,   W.,    LONDON.  391 

FIG.  2090.       FIG.  2112. 

FIG.  2092.        FIG.  2095. 

2091  Syphon,  Wurtemberg  (fig.  2091)     .       .       2s.  6d    5s. 

2092  Syphon,  Mitscherlich's,  suction  tube  with  bulb,  and 

end  bent  upwards  (fig.  2092)      ...        3s.  6d. 

2093  Ditto,  with  Stopcock 10s.  6d. 

2094  Syphon,  with  Negretti  and   Zambra's  adaptation  of 

Syringe,  useful  where  Acids,  &c.,  are  being 
drawn  off  (fig.  2094)      .        .        .        5s.  6d. 

FIG.  2094 

FIG.  2095* 

FIG.  2102. 

FIG.  2087.  FIG.  2095*.  FlG.  2097.        FlG.  2096. 








FIG.  2116*. 

FIG.  2121. 

FIG.  2118. 



FIG.  2122. 
£    s.    a. 
Syringes  of  Glass  (figs.  2095  and  2095*) .        .        .        .010 

Ditto,  with  bent  point  (fig.  2096) 

Thermometers,  various,  for  chemical  purposes  (figs.  2097, 2097*) 
see  also  pages  153  to  175)  insulated  in  glass  tube  3s.  6d.  0    5    6 
Test  Glasses,  Conical,  Clark's  pattern  (fig.  2098)          .008 
Test  Glasses,  Cylindrical,  for  lecture  table  (figs.  2099  and  2099*)  : 
Capacity  .  .  12-oz.  8-oz. 

Is.  6d.  Is.  4d. 

Ditto         ditto         Conical  form  : — 

Contents  .  .  2-oz.  4-oz.  6-oz. 

Price  8d.  lOd.  Is. 

Test  Mixer,  Graduated  and  Stoppered  for  quantitative 

analysis  (fig.  2101) 

Test  Tubes  (fig.  2102),  of  German  Glass,  free  from  lead,  carefully 

the  closed  end,  and  bordered  at  the  mouth  :— 


fin.        .        . 


l-in.        .        . 

|-in.        .        . 



Tube  Flasks    . 
Tube  Retorts  . 


0    1 
0    2 

s.    A. 


2  and  2^-in  

3,  3J.  4,  4|,  5,  and  6-in.     . 

4i,  5,  S&,  and  6-in.     . 

4,  5,  and  6-in  

5  and  6-in.         .... 

7  and  9-in.         * 

per  doz. 


.  each 





Is.  4d. 

rounded  at 

Per  Dozen. 


0  2  f 
0  3  ( 
0  4  £ 

0    6     0 

45,   CORNHILL,    E.G.,   AND    122,    REGENT   STREET,     VV.,    LONDON. 



e    \/ 

FIG.  212G. 

FIG.  2126*.   FIG.  2101.  FIG.  2109. 

FIG.  2127. 










Tubes    of   Berlin 
redness  :  — 

Length    . 

Price  . 

Porcelain,  for  containing   substances    to    be   heated  to 




4s.  6d.      5s.  6d. 


7s.  6d. 

24-in.  18-in. 

f-in.  1-in. 

7s.  6d.  10s.  6d. 

24-  in. 


Trays,  flat,  Porcelain,  for  washing  papers,  &c.      Is.  6d.  £0 
Ditto,  shallow,  G-lass       ......  from 

Tubes/three-limb  and  letter  Z,  for  ad  justing  apparatus 
to  the  exhausting  syringe  (fig.  2108)  .         .         .         .016 

Tubes,  long  Glass  conducting  U  shape  (fig.  2109)         . 
Turpentine    Bulbs,   of   glass,  for  containing  volatile 


substances  about  to  be  analysed  .  .  .  per  doz. 

Watch  Glasses per  doz. 

Water  Hammers  (fig.  2112) 

Ditto  ditto,  best  make  .  .  .  .  5s.  6d. 
Water  Baths,  for  drying  precipitates  or  explosive 

compounds,  stoneware  or  porcelain  .... 
Water  or  Oil  Bath,  of  Berlin  Porcelain,  especially 

adapted  for  drying  a  precipitate  contained  on  a  filter 
Water  Bottle,  stoppered,  with  glass  tap,  for  holding 

distilled  water,  &c. ;  also  useful  as  Aspirators 

(figs.  2116  and  2116*)  :— 

Contents       4-lb.  6-lb.  8-lb.  12-lb.  20-lb.  24-lb. 

Price        .  11s.  6d.  12s.  6d.     15s.        18s.         25s.         30s. 

Washing  Bottle,  Berzelius'  Fountain,  for  washing 
precipitates  by  a  continual  jet  of  water 

The  Tube  only  (fig.  2118) 

Washing  Bottles,  Gmelin's,  fitted  to  a  16-oz.  flask 

Washing  Bottle,  Syphon,  improved  form,  in  which  a 
current  of  water  is  supplied  continuously  . 

The  Tube  only  (fig.  2121) 

Washing  Bottle,  improved  form,  complete  with  sup- 
port, funnel  and  receiving  jar  (as  fig.  2122) 


020        040 
086        0  12    0 



0  1  6 

0  6  Q 
0  4  9 

0  16    0 



£      a.     d. 

056          076 

2123  Volumeter,  1,000  grains  capacity,  divided  into  100  equal 

parts  (fig.  2101) 

2124  Woulffe's  Bottles,  well  made  plain  necks,  so  as  to  cork 

easily ;  with  two  necks  shape  as  fig.  2124  : — 

Contents      i-lb.  1-lb.  2-lb.  4-lb.  6-lb.      8-lb.         10-lb. 

Price          .     Is.        Is.  6d.      2s.  6d.      3s.  8d.      5s.      7s.      8s.  6d. 

2125  Woulffe's  Bottles,  with  three  plain  necks,  shape  as  fig.  2125  :— 

Contents      £-lb.        1-lb.  2-lb.  4-lb.         6-lb.        8-lb.  10-lb. 

Price          .    2s.     2s.  6d.      3s.  4d.      4s.  8d.    6s.    9s.  6d.     11s.  6d. 

2126  Woulffe's  Bottles,  with  one  neck,  accurately  Stoppered, 

as  figs.  2126  and  2126°  :— 

l-pint.  2-pints.  3-pints. 

2-neck  3s.  2d.  3s.  8d.  4s.  6d. 

3-neck  3s.  8d.  4s.  6d.  5s.  6d. 

2127  WoulfFe's  Bottles,  a  set  of  three  l-pint,  in  a  Mahogany 

tray,  fitted  with  safety  funnels,  tubes  and  connectors 
(fig.  2127) 

0  18    6 

FIG,  2137. 

FIG.  2137*. 

FIG.  2145. 

FIG.   2138. 


£      s.     d.         £      s.     d. 

2128  Apparatus  for  illustrating  the  Composition  of  Water 

Synthetically,      by      burning     Hydrogen      gas     in 

atmospheric  air     ........  050 

2129  Berzelius'  Sulphuretted  Hydrogen  Apparatus 

(figs.  2129,  2129*) 086 

2130  Ditto,  ditto,  with  extra  Washing  Bottle,        ...  1  12    6 

2131  Cavendish's  Apparatus    for  detonating  a  mixture  of 

Oxygen      and      Hydrogen     Gas,     illustrating     the 

Composition  of  Water 2  12    6 

2132  Donavon's   Apparatus  for  Filtering    Caustic   Potash 

(fig.  2132) 1  10    0 

2133  Dobereiner's  Extracting  Apparatus  (fig.  2040)       .  1  15    0 

2134  Fritzch's  Apparatus,  for  Analysis  of  Carbonates  (fig.  2234)  020 

2135  Glass   Apparatus   for   showing    Diminished  Bulk  by 

mixing  Sulphuric  Acid  and  Water  (fig.  2135)      .  050 

2136  Glass  Apparatus,  for    Exhibiting    the    Philosophical 

Candle  and  producing  musical  sounds  by  Hydrogen 

Gas "      from  0  10     6 

2137  Leibig's    Potash  Apparatus,  made  very   light  from 

German  glass,  free  from  lead  (figs.  2137  and  2137*)   .026        036 

45,    CORNIIILL,    E.G.,    AND    122,    EEGENT    STREET,    W.,    LONDON".  395 

FIG.  2139.       FIG.  2140. 

2138  Mitscherlich's  Potash  Apparatus,  very  light,  (fig.  2138) 

2139  Marsh's  Apparatus  for  detecting  Arsenic  (fig.  2139)     . 

2140  Ditto,  ditto,  on  Stand  (fig.  2140) 

214 L  Clark's  Apparatus  for. detecting  Arsenic  (fig.  2141)     . 

2142  Percy's  Apparatus,  for  Analysis  of  Carbonates     . 

2143  Ure's  Apparatus    for   determining    the    quantity    of 

Nitrogen ..04 





FIG.  2132 

FIG.  2136. 

FIG,  2129* 



0    3 

0  7 
0  9 
0  10 

0    7 


Will  and  Varrentrap's  Nitrogen  Bulbs  .... 
Nitrogen  Bulb  with  Horsford's  Modification  (fig.  2145) 
Bell-Shaped  Dialyser  of  Glass,  with  two  Flanges 
Cylindrical  Glass  Jars,  for  using  above 
Dialysers,  Tube  Form,  Dr.  Alfred  S.  Taylor's  Form, 

for  testing  Mineral  Poisons 

Parchment  Paper,  for  use  with  Dialyser,  best  quality 

84  by  6  inch,  Is.  6d. ;  lOf  by  6  inch,  2s. ;  12  by  12  inch, 

2s.  6d. ;  14  by  12  inch,  3s.  6d.  per  dozen. 
Flat  Conical   Glass  Basins,  with  Spout  for  holding 

Distilled  Water  below  the  Dialyser,  and  collect  the 

Diffusate  3s.  6d.    0    5     6        06 


Sets  of  Chemical  Apparatus  and  Tests  adapted  for  the  Analysis  of  Soils, 
Manures,  &c.,  &c.,  or  for  the  examination  of  Adulterated  Articles  of  Focd 
fitted  up  to  ordir.  See  also  end  of  Chemical  Section,  page  411. 



FIG.  2153. 

Sets  of,  seepage  400. 


2151  Balances,  Chemical,  with  Glass  Cases,  highly  finished  and  carefully  adjusted, 

to  turn  with  T^th  of  a  grain  or  one  Milligramme 

£8  8s.      10  10    0        12  12    0 

2152  Balances,  Assay,  with   framed    beam  and    steel  knife,    edges  resting    on 

Agate  planes,  sliding  weight  on  beam,  with  adjustments,  in  Glass 
Lantern,  with  levelling  screws,  &c.,  of  the  most  delicate  accuracy,  to  turn 
with  TTJVoth  of  a  grain 15  15  0  25  0  0 

2153  Balances,  Assay  or  Chemical,  of  the  highest  precision,  fitted  with  all  recent 

improvements,  adjustments  and  appliances.  Plate  Glass  for  bottom 
of  the  case  (fig.  2153) £35  to  £50  0  0 

Decimal  Weight 

2154  Balance  (fig.  2154)  for  Assay- 
ing,  Analysis,  or  Diamond  weighing, 
will  carry  500  grains  and  turn  with 
-ji^th  of  a  grain ;  all  bearings  of  Steel. 
In  plain  Glass  Case,  with  -key  arrange- 
ment for  lifting         .         .£660 

Ditto     ditto  with  Set  Screws 
and  Spirit  Level        .        .£770 

2155  Balance   for  determining  the 
Specific  Gravity  of  Fluids,  whether 
heavier  or  lighter  than  water,  to  the 
third  place  of  decimals.  This  Balance 

consists   of   weigh-beam,   a    plunger  FIG.  2154. 

to  be  immersed  in  the  fluid ;  fitted  with  Thermometer,  Set  of  Weights  and  Riders, 

Glass  Solution  Jar,  &c.,  in  wood  case  price  £4  10    0 

45,    CORNHILL,    E.C.,    AND    122,    REGENT    STREET,    W.,    LONDON. 


FIG  2170.   FIGS.  2168, 

2171,  2167*,  2165,  2167  2166  2169,  2167* 












Balances  and  Scales  with  Weights,  for  Commercial,  rough  Laboratory,  or 

counter  use,  see  pages  405,  408. 
Balloons,  for  inflation  with  Hydrogen  or  Coal  Gas  : — 

Diameter      .      9-in.  10-in.  12-in.  16-in.  18-in.  20-in.  36-in. 

Price      .  Is.  6d.     2s.  6d.     3s.  6d.     4s.  6d.     5s.  6d.     8s.  6d.        36s. 

£    s.    d. 

Balloons,  oval  shape,  3-ft.  high  and  2-ft.  diameter 
Balloons,  fish  shape,  15-in.  and  30-in.  long     . 

Bladders,  mounted  with  Ferrules 

Ditto        ditto        and  Stop-Cock 076 

Bar  Compound,  for  showing  the  unequal  expansion  of 

metals  by  heat       ...!*.'. 
Bars  of  Antimony,  Bismuth,  Copper,  Iron,  Lead,  Tin, 

and  Zinc,  for  precipitating  metals  from  solution,  from 

Blowpipes,  common  Brass 010 

Ditto,  Black's  (fig.  2165) 010 

Ditto,  Bergman's  improved  (fig.   2166)  with  two  jets    . 
Blowpipes,    various  patterns  :     Berzelius'    (fig.  2167) ; 

Pepy's  (fig.  2167*)  with  movable  Jet,  for  use  at  any 

angle  ;  or  Wollaston's  Pocket  form  2167*     .         .  from   0  16     0 
Blowpipe,  Hemming's  Safety,  Oxy-Hydrogen  (fig.  2168) 
Blowpipe,  Oxy-Hydrogen,  complete  with  Lime-Holder, 

Stopcocks,  &c.,  (fig.  2169) 

Blowpipes,  Spirit,  Self-acting,  for  bending  glass  tubes, 

strong  Tin  (fig.2170) * 

Ditto        ditto,  Copper  Ball  (fig.  2171)    .... 
Blowpipe,  Self-acting,  Gas  and  Steam,  very  convenient 

and    powerful    for    small    solderings,   brazings,   or 

fusions  .......... 

Blowpipes,  Spirit,  or  Russian  Furnace   .... 

Ditto         ditto,  with  ring  and  support     .... 

Blowpipe,  Tilley's    Water  Pressure,   with  jets,   &c., 

complete,  in  japanned  tin     ...... 

Bruner's  Aspirator,  Japanned  Tin  or  Zinc  (see  fig.  78* 

page  72).     See  also  Water  Bottles 
Glass  Blower's  Table,  with  best  double-action  bellows, 

jointed  motion  to  jet-holder,  and  two  jets  (fig.  2177) . 
Glass  Blower's  Lamps  (figs.  2178  and  2178°) 
Spirit  Lamps,  of  glass  (fig  2179)     .... 

£    s.    d. 

0  18  6 
0  10  6 

050        0  12    6 



0  12  6 

0  12  6 

2  10  0 

0  10  6 

0  15  0 


0  15    0 

1  12    6 




FIG.  2177, 

2179*  Glass  Blower's  Apparatus,  Patent,  consisting  of  a 
circular  column  of  japanned  zinc,  table  covered  with 
zinc  (having  brass-bound  edges)  double -action  cir- 
cular bellows,  drawer,  and  universal  -jointed  iet 
(fig.  2179)  .  .  . 

2179f  Ditto        ditto        without  Zinc  cover  to  the  table 

FIG.  2179. 

£5  10    0 

FIG  2178. 

FIG.  2179. 

FIG. 2178" 

2180  Hot  Blast  Blowpipe,  for  temperatures  above  those  obtained  by  the  ordinary 
gas  and  air  blowpipe.  It  will  be  seen  by  the  wood-cut  (fig.  2180)  that  the 
tube  of  the  Air  Jet  is  coiled  round  the  gas  tube,  both  being  heated  by  a 
Bunsen  Burner  underneath,  each  being  controlled  by  separate  taps. 

The  jet  when  reduced  down  to  a  small  point  of  flame  is  nearly  equal  in  power 
to  the  Oxy-Hydrogen  Jet,  readily  fusing  a  moderately  thick  Platinum  "Wire. 
It  is  a  most  useful  arrangement  for  Chemical  Soldering,  and  general 
Workshop  use.  Price  16s.  6d. 

2181    Hand  Blower  (fig.  2181)  for  use  with  above 

0    16 

2182    Foot  Blowers,  for  Blowpipe  work,  Autogenous  Soldering  or  Furnace  use. 

21s.,  30s.,  35s. 

45,    CORNHILL,    E.G.,    AND    122,    EEGENT   STEEET,    W.,    LONDON. 


FIG.  2180. 

FIG.  2181. 

£    s.    d. 

2183  Blowpipe  Jets,  Platinum         ....         from 

2184  Blowpipe  Forceps  of  Brass  with  fine  points  . 

2185  Ditto    ditto    Steel  and  Platinum  Points      .       5s.  6d.     0     7     6 

2186  Ditto  Spoons,  Platinum  or  Silver  .         .         .          from 

2187  Blowpipe  Apparatus,  for  Pocket,  containing  requisites 

for  Assaying  metals,  in  case        ..... 

2188  Bellows,  portable  Double,  for  table  furnaces  .         from 

2189  Blowpipe,  Mineral  Fragments,  per  box  .... 

2190  Brass  Tobacco  Pipe,  for  blowing  Gas  Bubbles 

2191  Brushes,  Test  Tube         .....         from 

2192  Ditto,  Phial  and  Bottle  ......    8d.    0    0  10 

2193  Caoutchouc  in  sheets      ....... 

2194  Caoutchouc  Gas  Bags,  wedge  shape,  see  also  Lantern 

Section  ........         from 

2195  Ditto  Connectors,  for  joining  tube  apparatus         from 

2196  Ditto,  Vulcanised  Tube  .       .       .        .per  foot,  from    006 

2197  Ditto  Varnish  .......      per  oz. 

2198  Ditto  Water  Bottles       .......    0  10    6 

2199  Capsules   of   Platinum,  Silver,  Copper,  &c.,  various. 

2200  Chauffers  with  cover  and  pipe  for  increasing  heat         .    0  10    6 

2201  Chemical  Labels      .....  per  set    0    0    8 

2202  Combustion  Furnace  of  stout  Sheet  Iron 

2203  Cross  of  Four  Metals  for  showing  unequal  power  of 

conducting  heat    ........ 

2204  Connecting  Pieces,  Brass  Angle  and  T  Pieces,  Union 

Joints  for  uniting  Stop-Cocks,  &c.       .         Is.  Is.  6d.     0     2     6 

2205  Connecting  Ferrules,  Brass,  for  Bladders      .       .       .010 

2206  Crucibles,  Platinum,  Silver,  Iron,  &c.,  various. 

2207  Crucible  Jacket,  iron  plate,  to  hold  any  size  Platinum 

Crucible        ......... 

2208  Crucible  Stands  and  Supports,  various  .       .       .       .002 

2209  Ditto  Tongs,  straight,  bent,  &c.,  of  various  sizes  Is.  6d.     0    2    6 

£  s.  d 


0  10  6 

1  10  6 
1  10  0 

0  12  0 

1  10  0 


0  12  6 




Fletcher's  Blowpipes  and  Furnace  Apparatus  supplied  to  order. 



FIG.  2212. 


£  s.  a. 

£    a.    d 

0  10    6 

2211  Condensers,  Liebig's  form  for  Distillation  (fig.  2212) 

The  steam  passes  through  a  long  Glass  tube,  inclosed  in  an  outer  Metal  tube  ;  in  the  intervening  space 
water  is  made  to  flow  continuously,  and  rapid  condensation  is  effected. 

2212  Support  for  Liebig's  Condenser,  best  make,  in  wood, 

capable  of  being  elevated  and  inclined  to  any  angle 

(see  fig.  2212) •  0  10    6 

2213  Ditto  ditto,  Metal    .........  0  16    0 

2214  Adjustable  Wooden  Stand  for  water  vessel  (see  fig.  2212) 

2215  Cork  Borers,  a  set  of  four,  without  case        ...  026 

2216  Ditto,  of  polished  brass,  set  of  six,  in  a  case         .        .  046 

2217  Ditto,  a  set  of  twelve 076        0126 

2218  Deflagrating  Spoon,  the  bowl  rivetted  to  the  stem,  with 

a  sliding  cover  for  the  jar  (fig.  2218)  ....  008 

2219  Ditto,  Ground  Cover,  to  fit  the  top  of  Glass  Receiver  .  026 

2220  Drying  Apparatus,  or  Hot  Air  Bath,  on  stand,  japanned 

tin,  from 110 

2221  Ditto        ditto        «£  Copper,  or  Copper  tinned     .        .220        440 

2222  Decimal  Weights,  from  1,000  grains  to  a  10th  of  a  grain, 

in  mahogany  box 1  10     0 

2223  Ditto,  from  1,000  grains  to  1 -100th  of   a  grain,  the 

smaller  weights  of  Aluminium  or  Platinum        .  220 

2224  Diamonds,  for  Writing  and  Engraving  on  Glass    from  0  10     6 

2225  Ditto          for  Cutting  ditto 0  15     6  to  2    2    0 

2226  Dishes,  Evaporating,  Copper  ....         from  026 

2227  Ditto  ditto  Copper  tinned  inside          .  030 

2228  Ditto  ditto  Copper  plated  with  silver  .  066 

2229  Ditto  ditto  Silver.         .         .         .          from  0  12     6 

2230  Ditto        '    ditto  Enamelled  Iron          ...  026 

2231  Evaporating  Capsules,  of  Platinum : — 


l-in.  |-in.        1-in. 

l-16th  oz.    l-10th  oz.    i-oz. 





Price  variable,  according  to  weight,  about  35s.  per  oz. 

45,   CORNHILL,   E.G.,   AND    122,    BEGENT   STREET,   W.,   LONDON. 


FIG.  2257f. 

FIG.  2257*. 

2232  Files,  for  cutting  Glass  Tube,  with  wood  handle    . 

2233  Files  and  Rasps,  for  fitting  Corks  to  tubes,  with  wood 


2234  Flexible  Tube,  Metal,  for  conducting  gases,  from  per 


2235  Ditto        ditto        Vulcanised  India  Rubber 

2236  Filter  Paper,  very  thick  and  coarse        .... 

2237  Filter  Papers,   Circular,  ready  cut  for  use;  give  a 

very  minute  portion  of  ash,  and  filter  rapidly ;  in 
packets  of  100  :— 

Diameter    .        2]  -in.        2|-in.        2|-in.        4^-in 

Price  per  100    .        3d.        5d.        7d.        8d. 

2238  Filtering  Paper,  superior  quality,  per  quire    . 

2239  Ditto,  Swedish,  per  quire,  Munktell's  Genuine 

2240  Filter  Paper  Boxes,  japanned,  holding  200  filters:— 

For  No.  1  23456  Filters. 

7d.        8d.        9d.        Is.      Is.  3d.  Is.  6d. 

2241  Funnels,  Gutta  Percha from 

2241*  Ditto,  Ebonite veacl1 

2422     Ditto,  Tin  and  Tinned  Copper         .... 

2243  Furnaces,  Aikin's  blast  .        .        .        .        . 

2244  Furnaces,  Black's  Universal,  of  Sheet  Iron,  with  Cast 

Iron  fittings,  applicable  to  the  reduction  and  assay 
of  metallic  ores,  cupellation  of  silver,  &c.,  full  size    . 

2245  Furnaces,  portable  Table  Earthen  and  Black  lead,  from 

2246  Ditto,  Black  Lead,  larger,  for  retorts  or  tubes,  &c. 

2247  Furnaces,  round  Iron,  lined  with  fire  lute  or  brick, 

applicable  for  general  chemical  purposes    . 
2243*  Furnace  Blowers,  see  page  398. 
2244*  Forge,  improved  single  blast.     These  Forges  possess 

great  power,  and  are  very  portable      .         .      Round 
2245*  Forge,  Patent  double  Deck  or  Rivet,  having  large  powers 

of  blast,  insuring  great  and  rapid  heat  (fig.  2245)  Round 


Is.   Is.  4d. 



0  0  10 

0  2  0 

0  18  6 

5  10  0 
1  10  0 

330   550 



2  D 


FIG.   2247*. 











FIG.  2245*. 

£     s.    d. 


Forge,  improved  Portable  Iron,  adapted  for  soldering 

and  brazing  purposes,  jewellers'  uses,  and  suited  for 

amateur  mechanics Square     550        660 

Forge,  portable  Iron,  improved  with  double  bellows, 

the  whole  fitted  together  with  nuts  and  screws  for 

convenience  of  packing,  arranged  with  connecting 

screw  and  pipe  for  blast  furnaces  (fig.  2247*)     .  10  10    0 

A  most  useful  article  for  persons  residing  in  foreign  parts,  or  Emigrants.